Orosur Mining Inc. Pantanillo Norte Property, III Región, Chile NI 43

Transcription

Orosur Mining Inc.
Pantanillo Norte Property, III Región, Chile
NI 43-101 Technical Report
Prepared by:
Armando Simón, Ph.D., P.Geo (APGO)
Paula Larrondo, Member, (AusIMM)
Joyce Maycock, P.Eng. (APEGBC)
Francisco Castillo
Rustin Cabrera
Effective Date: 9 July, 2010
Prepared for:
Orosur Mining Inc.
Project No: 3107
October, 2010
IMPORTANT NOTICE
This report was prepared as a National Instrument 43-101 Technical
Report for Orosur Mining Inc. (Orosur) by AMEC International Ingeniería
y Construcción Limitada (AMEC).
The quality of information,
conclusions, and estimates contained herein is consistent with the level
of effort involved in AMEC’s services, based on: i) information available
at the time of preparation, ii) data supplied by outside sources, and iii)
the assumptions, conditions, and qualifications set forth in this report.
This report is intended for use by Orosur subject to the terms and
conditions of its contract with AMEC. This contract permits Orosur to
file this report as a Technical Report with Canadian Securities
Regulatory Authorities pursuant to National Instrument 43-101,
Standards of Disclosure for Mineral Projects. Except for the purposes
legislated under provincial securities law, any other uses of this report
by any third party is at that party’s sole risk.
Orosur Mining Inc.
Pantanillo Norte Property, III Region, Chile
CONTENTS
1.0 SUMMARY ................................................................................................................................... 1-1 1.1 Introduction ...................................................................................................................... 1-1 1.2 Ownership........................................................................................................................ 1-1 1.3 History.............................................................................................................................. 1-2 1.4 Geology and Mineralization ............................................................................................. 1-2 1.5 Exploration and Data Verification .................................................................................... 1-4 1.6 Metallurgy ........................................................................................................................ 1-5 1.7 Resource Estimation ....................................................................................................... 1-5 1.8 Conclusions ..................................................................................................................... 1-8 1.8.1 Geology, Exploration and Data Verification........................................................ 1-8 1.8.2 Resource Estimation ........................................................................................ 1-10 1.9 Recommendations ......................................................................................................... 1-11 2.0 INTRODUCTION .......................................................................................................................... 2-1 2.1 Purpose ........................................................................................................................... 2-1 2.2 Qualified Persons ............................................................................................................ 2-1 2.3 Sources of Information .................................................................................................... 2-2 2.4 Terms of Reference ......................................................................................................... 2-2 3.0 RELIANCE ON OTHER EXPERTS .............................................................................................. 3-1 4.0 PROPERTY DESCRIPTION AND LOCATION ............................................................................ 4-1 4.1 Location ........................................................................................................................... 4-1 4.2 Property Title in Chile ...................................................................................................... 4-1 4.3 Company Ownership, Agreements, and Mining Claims .................................................. 4-2 4.4 Surface Rights ................................................................................................................. 4-4 4.5 Water Rights .................................................................................................................... 4-5 4.6 Environmental and Socio-Economic Issues .................................................................... 4-5 5.0 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND
PHYSIOGRAPHY ......................................................................................................................... 5-1 5.1 Accessibility ..................................................................................................................... 5-1 5.2 Physiography, Climate, Vegetation and Fauna ............................................................... 5-1 5.3 Local Resources and Infrastructure ................................................................................ 5-2 5.4 An Overview of Chile ....................................................................................................... 5-3 5.4.1 Introduction ......................................................................................................... 5-3 5.4.2 Geography .......................................................................................................... 5-3 5.4.3 Climate................................................................................................................ 5-6 5.4.4 Demography ....................................................................................................... 5-6 5.4.5 Political ............................................................................................................... 5-7 5.4.6 Economy and Business Investment Climate ...................................................... 5-8 5.4.7 Mineral Resource Data ....................................................................................... 5-9 5.4.8 Chilean Mining .................................................................................................. 5-10 5.4.9 Mineral Royalty Law ......................................................................................... 5-11 6.0 HISTORY ...................................................................................................................................... 6-1 7.0 GEOLOGICAL SETTING ............................................................................................................. 7-1 7.1 Introduction ...................................................................................................................... 7-1 7.2 Regional Geology and Tectonic Evolution ...................................................................... 7-1 Project No. 3107
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7.3 7.2.1 Regional Geology ............................................................................................... 7-1 7.2.2 Tectonic Evolution .............................................................................................. 7-3 Local Geology .................................................................................................................. 7-4 7.3.1 Stratigraphy and Magmatism.............................................................................. 7-4 7.3.2 Alteration............................................................................................................. 7-7 7.3.3 Structure ............................................................................................................. 7-8 8.0 DEPOSIT TYPES ......................................................................................................................... 8-1 9.0 MINERALIZATION........................................................................................................................ 9-1 10.0 EXPLORATION .......................................................................................................................... 10-1 10.1 Anaconda Pre-1983 Exploration ................................................................................... 10-1 10.2 AA 1983 to 1998 Exploration ......................................................................................... 10-1 10.3 Kinross 2005-2008 Exploration ..................................................................................... 10-1 10.4 Orosur 2010 Exploration................................................................................................ 10-3 10.4.1 Surveying .......................................................................................................... 10-3 10.4.2 Drilling ............................................................................................................... 10-3 10.4.3 Re-sampling ..................................................................................................... 10-3 11.0 DRILLING ................................................................................................................................... 11-1 11.1 Anaconda Pre-1983 Drilling........................................................................................... 11-1 11.2 AA 1988 to 1998 ............................................................................................................ 11-1 11.3 Kinross 2006 to 2008 ..................................................................................................... 11-3 11.4 Orosur 2010 ................................................................................................................... 11-4 11.4.1 Core Drilling and Logging ................................................................................. 11-5 11.4.2 RC Drilling and Sampling ................................................................................. 11-5 11.4.3 Significant Mineral Intersections ....................................................................... 11-7 11.4.4 Exploration Potential......................................................................................... 11-7 12.0 SAMPLING METHOD AND APPROACH .................................................................................. 12-1 12.1 AA 1988 to 1998 ............................................................................................................ 12-1 12.2 Kinross 2006 to 2008 ..................................................................................................... 12-1 12.3 Orosur 2010 ................................................................................................................... 12-1 13.0 SAMPLE PREPARATION, ANALYSES, AND SECURITY ........................................................ 13-1 13.1 AA 1988 to 1998 ............................................................................................................ 13-1 13.2 Kinross 2006 to 2008 ..................................................................................................... 13-1 13.3 Orosur: 2010 .................................................................................................................. 13-1 14.0 DATA VERIFICATION ................................................................................................................ 14-1 14.1 Drill-Hole Collar Review................................................................................................. 14-1 14.2 Database Checks .......................................................................................................... 14-2 14.2.1 Hard-Copy Drill-Hole Folders ........................................................................... 14-2 14.2.2 Collar and Down-Hole Surveys ........................................................................ 14-2 14.2.3 Original Logs: Lithology, Alteration and Mineral Zone ..................................... 14-2 14.2.4 Original Certificates .......................................................................................... 14-3 14.3 Core Description and Geological Interpretation ............................................................ 14-3 14.4 Down-Hole Contamination Analysis .............................................................................. 14-3 14.4.1 Decay................................................................................................................ 14-4 14.4.2 Cyclicity............................................................................................................. 14-5 14.5 Twin Holes ..................................................................................................................... 14-6 14.6 QC Protocols and Data.................................................................................................. 14-6 Project No. 3107
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14.7 14.6.1 Definitions ......................................................................................................... 14-6 14.6.2 AMEC QC Evaluation Processing .................................................................... 14-8 14.6.3 AA QC 1988 to 1998 ........................................................................................ 14-9 14.6.4 Kinross QC 2006 to 2008 ............................................................................... 14-11 14.6.5 Orosur QC 2010 ............................................................................................. 14-12 Density Review ............................................................................................................ 14-17 15.0 ADJACENT PROPERTIES ........................................................................................................ 15-1 16.0 MINERAL PROCESSING AND METALLURGICAL TESTING .................................................. 16-1 17.0 MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES............................................. 17-1 17.1 Definitions ...................................................................................................................... 17-1 17.2 Drilling Database ........................................................................................................... 17-1 17.3 Geological Model and Definition of Domains ................................................................ 17-3 17.4 Composites .................................................................................................................... 17-5 17.5 Exploratory Data Analysis ............................................................................................. 17-5 17.5.1 Basic Statistics ................................................................................................. 17-5 17.5.2 Contact Analysis ............................................................................................. 17-14 17.6 Variography ................................................................................................................. 17-15 17.7 Restriction of Extreme High-Grade Values ................................................................. 17-15 17.8 Block-Model Dimensions and Grade Estimation ......................................................... 17-16 17.8.1 Estimation Plan ............................................................................................... 17-17 17.9 Density ......................................................................................................................... 17-20 17.10 Block-Model Validation ................................................................................................ 17-21 17.10.1 Drift Analysis ................................................................................................... 17-22 17.10.2 Smoothing ...................................................................................................... 17-23 17.11 Resource Classification and Tabulation ...................................................................... 17-27 18.0 OTHER RELEVANT DATA AND INFORMATION ..................................................................... 18-1 19.0 ADDITIONAL REQUIREMENTS FOR TECHNICAL REPORT ON DEVELOPMENT
PROPERTIES AND PRODUCTION PROPERTIES .................................................................. 19-1 20.0 INTERPRETATION AND CONCLUSIONS ................................................................................ 20-1 20.1 Geology, Exploration and Data Verification................................................................... 20-1 20.2 Metallurgy ...................................................................................................................... 20-2 20.3 Resource Estimation ..................................................................................................... 20-3 21.0 RECOMMENDATIONS .............................................................................................................. 21-1 22.0 DATE AND SIGNATURE PAGE ................................................................................................ 22-1 23.0 REFERENCES ........................................................................................................................... 23-1 TABLES
Table 1-1: Drilling Summary ...................................................................................................................... 1-5 Table 1-2: Mineral Resources for Pantanillo Project ................................................................................. 1-7 Table 1-3: Recommended Drilling Program for the Pantanillo Norte Property ....................................... 1-12 Table 1-4: Estimated Budget for the Drill Program and Related Activities for the 2011-2012 Field
Seasons for the Pantanillo Norte Property........................................................................... 1-12 Project No. 3107
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Table 4-1: AANSA Mining Properties Granted in Option or Promise to Purchase to FV (Carey,
2010a) .................................................................................................................................... 4-3 Table 4-2: Schedule of Payments and Minimum Expenditures (Carey, 2010a) ..................................... 4-3 Table 5-1: Chilean Metallic Production – 2002 to 2009 (selected commodities) .................................. 5-11 Table 11-1: Drilling Summary .................................................................................................................. 11-1 Table 11-2: Logging Codes Used by Kinross in Core and RC Logging .................................................. 11-4 Table 11-3: Logging Codes Used by Orosur in Core and RC Logging ................................................... 11-6 Table 11-4: Significant Mineral Intersections in Selected Drill Holes ...................................................... 11-7 Table 13-1: Elements and Grade Ranges of ALS Assay Methods ......................................................... 13-1 Table 13-2: Elements and Grade Ranges of ACME Method Group 1E.................................................. 13-2 Table 14-1: Collar Coordinate Check (Corrected PSAD-56 Measurements) ......................................... 14-1 Table 14-2: Summary of Au Decay data at Various Grade Thresholds .................................................. 14-5 Table 14-3: AA Check Assay RMA Regression Statistics..................................................................... 14-10 Table 14-4: 2010 Resampling Test of AA Pulps: Au SRM Summary ................................................... 14-11 Table 14-5: Kinross 2008 Campaign Au SRM Summary ...................................................................... 14-12 Table 14-6: Orosur 2010 Campaign: Duplicate Summary .................................................................... 14-13 Table 14-7: Orosur 2010 Campaign SRM Summary ............................................................................ 14-15 Table 14-8: Bulk Density Summary ....................................................................................................... 14-18 Table 16-1: Summary of Bottle-Roll Tests (Source: Kinross) ................................................................. 16-2 Table 17-1: Summary of Drill Data Used for the Pantanillo Mineral Resource Estimate ........................ 17-2 Table 17-2: Lithological Unit Description ................................................................................................. 17-3 Table 17-3: Comparison of Lithogical Model to Logged Lithology .......................................................... 17-4 Table 17-4: Definition of Estimation Domains - Gold .............................................................................. 17-4 Table 17-5: Definition of Estimation Domains - Copper .......................................................................... 17-4 Table 17-6: Definition of Estimation Domains - Arsenic .......................................................................... 17-5 Table 17-7: Sample Statistics for Gold Assays by Lithological Unit........................................................ 17-5 Table 17-8: Sample Statistics for Copper Assays by Lithological Unit ................................................... 17-6 Table 17-9: Sample Statistics for Arsenic Assays by Lithological Unit ................................................... 17-6 Table 17-10: Sample Statistics for Gold by Lithological Inside Grade Shell ........................................... 17-6 Table 17-11:Sample Statistics for Copper by Lithological Inside Grade Shell ........................................ 17-6 Table 17-12:Sample Statistics for Arsenic by Lithological Inside Grade Shell ........................................ 17-6 Table 17-13: Sample Statistics for Gold by Lithological Outside Grade Shell ........................................ 17-7 Table 17-14: Sample Statistics for Copper by Lithological Outside Grade Shell .................................... 17-7 Table 17-15: Sample Statistics for Arsenic by Lithological Outside Grade Shell .................................... 17-7 Table 17-16: Sample Statistics for Gold by Mineralization Inside Grade Shell ....................................... 17-7 Table 17-17: Sample Statistics for Copper by Mineralization Inside Grade Shell ................................... 17-7 Table 17-18: Sample Statistics for Arsenic by Mineralization Inside Grade Shell .................................. 17-8 Table 17-19: Sample Statistics for Gold by Mineralization Outside Grade Shell .................................... 17-8 Table 17-20: Sample Statistics for Copper by Mineralization Outside Grade Shell ................................ 17-8 Table 17-21: Sample Statistics for Arsenic by Mineralization Outside Grade Shell ................................ 17-8 Table 17-22: Sample Statistics for Gold by Domains .............................................................................. 17-9 Table 17-23: Sample Statistics for Copper by Domains.......................................................................... 17-9 Table 17-24: Sample Statistics for Arsenic by Domains ......................................................................... 17-9 Table 17-25: Block Model Dimensions .................................................................................................. 17-16 Table 17-26: Estimation Parameters for Gold ....................................................................................... 17-18 Project No. 3107
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Table 17-27: Estimation Parameters for Total Copper .......................................................................... 17-18 Table 17-28: Estimation Parameters for Total Arsenic.......................................................................... 17-19 Table 17-29: Average Density Values for the Pantanillo Norte Resource Model ................................. 17-21 Table 17-30: Comparison of Composite Statistics with OK and NN Estimates for Gold ...................... 17-21 Table 17-31: Comparison of Composite Statistics with OK and NN Estimates for Copper .................. 17-22 Table 17-32: Comparison of Composite Statistics with OK and NN Estimates for Arsenic .................. 17-22 Table 17-33: Parameters for Open-Pit Resource Classification ........................................................... 17-28 Table 17-34: Optimization Parameters for Open-Pit Resource Shell.................................................... 17-30 Table 17-35: Mineral Resources by Mineralization Domains ................................................................ 17-31 Table 21-1: Recommended Drilling Program for the Pantanillo Norte Property ................................... 21-2 Table 21-2: Estimated Budget for the Drill Program and Related Activities for the 2011-2012 Field
Seasons for the Pantanillo Norte Property........................................................................... 21-2 FIGURES
General Location Map (After Siddeley, 2009) ........................................................................ 4-1 Summary Land Tenure Map (Carey, 2010a) ......................................................................... 4-4 Map of Chile ........................................................................................................................... 5-4 Schematic Geologic Map of the Maricunga Belt (Source: Davidson and Mpodozis, 1991,
quoted by Muntean and Einaudi, 2001). ................................................................................ 7-2 Figure 7-2: Simplified Geologic Map of the Pantanillo Prospect (Source: Kinross, quoted by Siddeley,
2009) ...................................................................................................................................... 7-5 Figure 7-3: Geologic Map of the Pantanillo Norte Property (Source: Orosur) ......................................... 7-6 Figure 7-4: Principal Structural Features of the Pantanillo Property (After Callan, 2006)........................ 7-9 Figure 8-1: Generalized Model of the Maricunga Porphyry-Epithermal Environment (After Vila and
Silitoe, 1991). ......................................................................................................................... 8-1 Figure 9-1: Time-space Diagram for Typical Magmatic-hydrothermal Systems in the Maricunga Belt
(After Muntean and Einaudi, 2001). ....................................................................................... 9-2 Figure 11-1: Drilling Plan by Campaigns .................................................................................................. 11-2 Figure 11-2: Scissor-type drilling by Kinross (After Siddeley, 2009) ........................................................ 11-3 Figure 14-1: ACME versus Geolab RMA Plot ........................................................................................ 14-10 Figure 14-2: Orosur 2010 Campaign Au in Twin Samples and Field Duplicates ................................... 14-13 Figure 14-3: Orosur 2010 Campaign Cu in Twin Samples and Field Duplicates ................................... 14-14 Figure 14-4: Orosur 2010 Campaign Au in Pulp Duplicates .................................................................. 14-14 Figure 14-5: Orosur 2010 Campaign: Cu in Pulp Duplicates ................................................................. 14-15 Figure 14-6: Orosur 2010 Campaign Au Accuracy Plot ......................................................................... 14-16 Figure 14-7: Orosur 2010 Campaign Cu Accuracy Plot ......................................................................... 14-16 Figure 14-8: Bulk Density vs. Depth for Major Rock Types ................................................................... 14-18 Figure 17-1: Difference between Topography versus Collar Elevation .................................................... 17-2 Figure 17-2: Box Plot for Gold Assays ................................................................................................... 17-10 Figure 17-3: Box-Plot for Copper Assays ............................................................................................... 17-11 Figure 17-4: Box Plot for Arsenic Assays ............................................................................................... 17-11 Figure 17-5: Box Plot for Gold Domains ................................................................................................. 17-12 Figure 17-6: Box Plot for Copper Domains ............................................................................................ 17-12 Figure 4-1: Figure 4-2: Figure 5-1: Figure 7-1: Project No. 3107
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Figure 17-7: Box Plot for Arsenic Domains ............................................................................................ 17-13 Figure 17-8: Cumulative Frequency Distribution for Gold - BXG unit (Assays) ..................................... 17-14 Figure 17-9: Contact Plot for Gold BXG - BXI ........................................................................................ 17-15 Figure 17-10: Probability Plots Au-Domains ......................................................................................... 17-16 Figure 17-11: Box Plot for Density......................................................................................................... 17-20 Figure 17-12: Drift Analysis – Au1 in EU1, EU2 and EU3 (NW-SE orientation) ................................... 17-23 Figure 17-13: Drift Analysis – Au2 in EU4 Domain (NE-SW orientation) .............................................. 17-23 Figure 17-14: Herco Analysis Pantanillo Norte: EU1, EU2, EU3 Domains ........................................... 17-25 Figure 17-15: Herco Analysis Pantanillo Norte: EU4 Domain ............................................................... 17-25 Figure 17-16: Vertical Section 5NW with Blocks and Assay Grades for Gold (50 m Corridor). ............ 17-26 Figure 17-17: Plan View at Elevation 4,450 m Showing High-Grade Extrapolation. ............................ 17-27 Figure 17-18: Section 10NW - Resource Classification ........................................................................ 17-28 Figure 17-19: Plan View 4,500m - Resource Classification .................................................................. 17-29 Figure 17-20: Section 5NW Showing the Outline of the Resource Pit .................................................. 17-32 UNITS
OF
MEASURE
Above mean sea level (used to express altitude) ....................................... amsl
Day ............................................................................................................... d
Days per year (annum) ............................................................................. d/a
Degree........................................................................................................... °
Degrees Celsius ......................................................................................... °C
Gram ............................................................................................................ g
Grams per tonne ........................................................................................ g/t
Greater than ................................................................................................. >
Hectare ....................................................................................................... ha
Hour .............................................................................................................. h
Hours per day ............................................................................................ h/d
Kilo (thousand) ............................................................................................. k
Kilometer ................................................................................................... km
Less than ...................................................................................................... <
Micrometre (micron) .................................................................................. µm
Milligram .................................................................................................... mg
Milligrams per litre .................................................................................. mg/L
Millilitre ...................................................................................................... mL
Millimetre .................................................................................................. mm
Million .......................................................................................................... M
Minute (time) ............................................................................................ min
Month ........................................................................................................ mo
Ounce ......................................................................................................... oz
Ounces per (short) ton ............................................................................ oz/st
Parts per billion......................................................................................... ppb
Parts per million....................................................................................... ppm
Percent ........................................................................................................ %
Pound .......................................................................................................... lb
Short ton (2,000 lb)…………………………………………………………..…..st
Specific gravity .......................................................................................... SG
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Tonnes per year………………………………………………………..……..…t/a
Year (annum) ............................................................................................... a
ABBREVIATIONS
American Society for Testing and Materials ........................................ ASTM
Association of Professional Geoscientists of Ontario……………..…….APGO
Australian Institute of Geoscientists…………………………………………..AIG
Canadian Institute of Mining and Metallurgy ............................................ CIM
Global Positioning System ...................................................................... GPS
Internal Rate of Return ............................................................................. IRR
Joint Ore Reserve Committee ………………………………………..….. JORC
Net Present Value ................................................................................... NPV
Rock Quality Designation ....................................................................... RQD
Universal Transverse Mercator .............................................................. UTM
Reverse Circulation ................................................................................... RC
Diamond Drilling ........................................................................................ DD
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1.0
SUMMARY
1.1
Introduction
Orosur Mining Inc. (Orosur) retained the services of AMEC International Ingeniería y
Construcción Limitada (AMEC) to prepare a National Instrument 43-101 (NI 43-101)
Technical Report (the Technical Report), as defined by CSA (2005a, 2005b, 2005c),
covering its Pantanillo Norte Au property (the Property), located in the III Region,
Northern Chile.
Dr. Armando Simón, P.Geo (AIG, APGO), Principal Geologist Paula Larrondo
(MAusIMM), and Joyce Maycock, P.Eng. (APEGBC), Project Manager, from the
AMEC Santiago Office, served as the Qualified Persons responsible for the
preparation of the Technical Report in compliance with Form 43-101F1 (CSA, 2005d).
In addition, Dr. Rustin Cabrera reviewed the historic data and exploration, and
conducted the data verification, and Francisco Castillo prepared the resource estimate
under Mrs. Larrondo’s supervision.
The scope of work for the project included an initial review of the available information
and work procedures, the preparation of the geological model and a resource
estimate, and the preparation of the Technical Report. Only limited metallurgical test
work was available, and as such AMEC has provided a brief review of metallurgy.
AMEC understands that the Technical Report will be used by Orosur in support of
filings with the TSX Venture Exchange.
1.2
Ownership
Orosur Mining Inc., formerly Uruguay Mineral Exploration Inc. (UME)1, is quoted in
Canada (TSX Venture Exchange: OMI) and London (AIM: OMI). On 8 November
2009, UME and Fortune Valley Resources Inc. (FV) signed an agreement to combine
their respective businesses. According to this agreement, UME agreed to acquire all of
the issued and outstanding common shares of FV2.
FV entered into a Staged Purchase Agreement with Anglo American Norte S.A
(AANSA) on 1 October 2009, which entitles FV to the option to purchase the group of
mining concessions covering the Property. Pursuant to the Stage Purchase
Agreement, FV is obliged to pay AANSA a total of US$850,000 and to complete a
minimum expenditure of US$4,000,000 and 12,500 m drilling. In addition to option
1. The UME Corporate name was modified to Orusur Mining Inc. On 7 January 2010 as per Certificate of
Ammendment. Issued b y Yukon Community Services.
2. www.orosur.ca/news/index.php?&content_id=67
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payments, the agreement also includes a net smelter return (NSR) of 3.5% or
US$300,000 per year for period 2013 to 2015, and a minimum NSR of 1 US$ million
per year from 2015 onwards.
Orosur is currently conducting a scoping Study. To date, no surface or water rights
have been acquired.
1.3
History
Empresa Minera Mantos Blancos (EMMB), a Chilean subsidiary of Anglo American
(AA), acquired the Pantanillo concessions in 1983, and explored the area intermittently
through the 1990’s. In 1997, prior to the enactment of NI 43-101, EMMB completed a
resource estimate of 640,000 oz Au in the Pantanillo Norte prospect, considered as a
historic estimate. In the mid-2000’s Kinross optioned the Property from AA, and
conducted soil and rock geochemical surveys, geological mapping and trenching over
40 km2.
In a number of campaigns carried out from 1987 to 2008, AA, EMMB and Kinross
drilled a total of 7,879 m (30 holes) reverse circulation (RC), 6,743 m (17 holes)
diamond drilling (DD) and 700 m (one hole) combined RC/DD in the Pantanillo Norte
prospect. With these data, Kinross completed in 2007 a non-43-101-compliant
resource of 96 Mt averaging 0.70 g/t at 0.5 g/t Au cut-off, or 2.2 Moz Au.
In early 2010, following the merger between UME and FV, Orosur conducted a drilling
program totalling 3,785 m in 19 DD holes and 1,854 m in 11 RC holes. This report
includes a new NI 43-101-compliant resource estimated based on the AA, Kinross and
Orosur drilling.
No formal historical production has been reported in the area, although isolated
pirquineros have periodically mined outcropping silica “ledges” that locally contain gold
grades exceeding 5 g/t.
1.4
Geology and Mineralization
The Property lies on the eastern flanks of the Azufre/ Copiapó volcanic complex. The
complex is composed of hydrothermally altered volcaniclastic units of mainly dacitic
and locally rhyolitic composition, with an estimated thickness exceeding 2,000 m. The
complex dips sub-horizontally to shallowly northward or eastward.
The volcanic sequence was intruded by a flow-dome complex composed of a series of
compositionally closely-related, feldspar-hornblende-(biotite-quartz) porphyritic units,
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interpreted as a high-level felsic flow-dome complex. This complex exhibits a northwest-elongated, slightly oval shape, reflecting the main direction of controlling
structures, and covering approximately 2.5 km2.
A series of WNW-ESE (locally NW-SE)-striking, sub-vertically dipping breccia units
have been mapped in the area. These units, showing pervasive advanced-argillic
alteration, exhibit tabular to locally irregular geometry, and reach up to 50 m width. The
breccias postdate the formation of the Au-porphyry mineralization, as suggested by the
presence of veinlet-mineralized porphyry clasts in the breccia.
Quartz-alunite ledges are commonly found on the Property, closely resembling the
shape of the breccias units. The ledges are less than 1 m to over 20 m thick, and may
reach up to 600 m in length, although they are usually shorter. Quartz may be compact
or vuggy, sometimes showing traces of native sulphur, barite and both specular and
earthy red hematite when close to surface. The quartz-alunite ledges have a close
spatial relationship with the breccia units.
A post-mineralization ignimbritic sequence, lacking hydrothermal alteration, covers the
mineralized and hydrothermally altered volcanic and flow-dome units discordantly and
with sub-horizontal dip.
The main types of alteration identified on the Property are as follows:
•
Structurally controlled, quartz-alunite-pyrite-hematite ledges with advanced argillic
± silicified selvages widespread kaolinite-goethite-hematite (after pyrite)-bearing
argillic assemblages associated with the uppermost andesite porphyry volcanic unit
•
Widespread chlorite ± magnetite ± pyrite ± silica alteration, associated with the
porphyry andesite and breccia intrusions
•
Advanced argillic alteration selvages around the late phreato-magmatic breccias.
Bedding in stratified volcaniclastic sequences and flow-banding in the upper portions
of the flow-dome complex generally shows shallow N to NE dips. The Property is
located on the SE projection of a 30 km long, regional-scale NW-SE- striking structural
zone linking the La Pepa high-sulphidation ledges and underlying Au porphyry system,
and the high-level breccia-hosted and porphyry-type Au mineralization at El Volcán
The Au mineralization is controlled by the above-mentioned structures, as well as by
NNW-SSE and ENE-WSW trending structures. Porphyry dyke swarms have a
predominant NW-SE strike, with moderate to steep dips between 50º-75º to SW. The
structural control is also pronounced within robust quartz-alunite-pyrite mineralized
ledges.
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Gold mineralization is mainly in sheeted-vein sets and weak stockwork networks of
quartz veinlets, which show textures similar to those documented in other Au-rich
porphyry systems in the Maricunga Belt. The gold grade in drill-core intersections with
strong banded-vein intensity commonly range from 1.0 g/t to 4.0 g/t. Quartz-alunite
ledges are discontinuous and volumetrically restricted, and ledge-hosted Au
mineralization on the Property is erratic, although grades may locally reach up to 2.5
g/t Au.
Oxide, mixed and sulphide mineralization-types have been described for the Property
on the basis of weathering state..
Oxide mineralization is mainly within intensely weathered porphyry andesite and
locally andesite breccia. The depth of oxidization is variable, but generally extends to
170 m to 190 m depth on the east side of the Property, and 40 m to 60 m depth on the
west side of the Property.
The mixed zone is hosted by both porphyry andesite and andesite breccia, with zones
of weak to moderate chlorite ± magnetite ± pyrite ± silica alteration inter-fingered with
moderate to weak weathering. Depths of mixed mineralization are variable, but
generally the mixed zone is located between 190 m and 310 m depth on the east side
of the Property, and between 60 m and 280 m on the west side of the Property.
The sulphide zone is mainly hosted by the breccia complex, with moderate to strong
chlorite ± magnetite ± pyrite ± silica alteration. The proportion of disseminated
magnetite and pyrite typically increases to up to 10%. The upper limit of the sulphide
zone is variable, but is generally greater than 310 m deep on the east side of the
Property, and below the 280 m depth on the west side of the Property.
A 0.3 g/t Au grade-shell representation of the mineralization on the Property has two
main, very irregular bodies, and a series of smaller bodies, which taken as a whole,
cover a broad mineralized zone over 850 m long (NW-SE) and 300 m wide, dipping
30° to 45° to the south-west. Mineralization has been intersected to 600 m depth, and
is open downward.
1.5
Exploration and Data Verification
In total, 20,531 m in 78 drill holes have been drilled on the Property since 1988. Of
these, 36 holes (10,528 m) were DD, 41 holes (9,303 m) were RC, and 1 hole (700 m)
was pre-collared with RC and extended to final depth with DD. Details of the drilling
programs are summarized in Table 1-1.
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Orosur Mining Inc.
Table 1-1: Drilling Summary
Company
Drill Hole
Prefix
Period
Anglo
American
EMMB
1997-1998
Kinross
2006-2008
Kinross
Kinross
2006
2006
Orosur
2010
Orosur
2010
1988
Total
Holes
DDHPN01-03,
05,06
SR97PN-01 to 22
DDHPN-10, 16,
PN-01 al 10
ARPN-01, 03-09
ARDDH-PN-02
PNN-10-01-06, 0810, 12-13,15, 2122, 26-30DDH
PNN-10-07, 11, 14,
16-20, 23-25RC
Total
Total
(m)
Length
Min
Max
(m)
(m)
Average
(m)
Drilling
Type
5
1,138
157
247
228
DDH
22
4,825
138
250
219
RC
12
5,605
297
540
467
DD
8
1
2,624
700
192
414
328
700
RC
RC/DD
19
3,785
120
267
199
DD
11
1,854
30.5
250
169
RC
78
20,531
268
During the preparation of this Technical Report, AMEC reviewed on site the surface
geology, as well as the drilling, core handling, logging and sampling procedures, drillhole surveying, and sample security procedures for current and previous exploration
campaigns. An assessment was made of the quality of these data and procedures
relative to industry standard practices.
AMEC is of the opinion that additional exploration potential exists in the deeper
horizons to south-west, where the sulphide mineralization has not been delimited. In
addition, some additional potential exists under the ignimbrite cover at the southeastern portion of the property.
1.6
Metallurgy
The limited metallurgical studies available on orientation samples indicated that the
Pantanillo Norte oxide could be highly amenable to cyanide leaching, as might be
expected. The sulphide zones gave poor cyanide leach results and the mixed “ores”
were in-between. It should be noted that the recoveries may have been partially
influenced by the “head grade” of the samples which was higher in the oxide and
mixed material.
1.7
Resource Estimation
Using geological interpretations prepared by Orosur, AMEC digitized the lithological
and mineralization models, as well as the 300 ppb gold grade-shell model in vertical
sections, and prepared level plans for the grade shells. Sections were oriented at
011° azimuth (NNE), and spaced 50 m apart. Bench plans were created at 50 m
intervals.
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AMEC reconciled interpreted shapes on vertical sections and level plans and
constructed solid models for the main lithological mineralization domains and for the
grade shell. AMEC utilized a combination of four different mineralization types,
including leached, oxide, mixed and sulphide mineralization, and three different
lithologies, including HS ledge breccias, intrusive breccias and andesitic porphyry,
both inside and outside the grade shell to defined estimation domains.
For grade estimation, AMEC used ordinary kriging for all domains, with correlograms
defined by domains inside and outside grade shell over 300 ppb gold.
Once grades were estimated, blocks classified into resource categories according to
grade continuity and confidence on the estimate. AMEC prepared a pit optimization to
constrain resources that have reasonable prospects of economic extraction by open pit
mining methods.
AMEC reported the mineral resources for Orosur according to CIM Definitions
Standards (CIM, 2005) Table 1-2 summarizes the resources using a 0.3 g/t Au cutoff
for oxide and mixed cutoff, and 0.5 g/t Au cutoff for sulphide.
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October 2010
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Orosur Mining Inc.
Table 1-2: Mineral Resources for Pantanillo Project
Ore
Type
Cutoff
Au
(g/t)
Measured
Indicated
Measured + Indicated
Inferred
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
Oxide
0.3
0.72
19,806
456,349
0.55
1,752
30,963
0.70
21,558
487,708
0.39
124
1,558
Mixed
0.3
0.7
16,011
361,246
0.65
8,336
173,619
0.68
24,348
534,865
0.62
180
3,608
Sulphide
0.5
0.72
748
17,328
0.68
440
9,566
0.70
1,187
26,894
0.00
0
0
0.71
36,565
834,924
0.63
10,528
214,148
0.69
47,093
1,049,071
0.53
304
5,166
Total
1 2
1
Totals may differ slightly from sum or weighted sum of numbers due to rounding.
2 Mineral resources are reported within a Lerchs-Grossman (LG)-optimized pit shell using Whittle® software with a gold price of 1,035 US$/oz; mining
cost of 1.65 US$/t; processing cost of 4.0 US$/t; general and administration cost of 1.0 US$/t, and recoveries of 75% for leached and oxide ore types,
65% for mixed ore, and 50% for sulphide ore.
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AMEC is of the opinion that the oxide and mixed ore types are reasonably well
investigated, and that the resource estimate shows acceptable results for total gold
values; however, AMEC recommends drilling infill holes in the high grade portion of the
deposit to increase the mineral resource confidence classification and to provide
information on the continuity of mineralization.
1.8
Conclusions
1.8.1
Geology, Exploration and Data Verification
The Pantanillo property lies on the eastern flanks of the Azufre/ Copiapó volcanic
complex, within a mainly dacitic to locally rhyolitic composition, hydrothermally altered
volcaniclastic units. The volcanic sequence was intruded by a flow-dome complex
composed of feldspar-hornblende-(biotite-quartz) porphyritic units with a NW-SEelongated, slightly oval shape covering approximately 2.5 km2.
A series of WNW-ESE (locally NW-SE)-striking, sub-vertical breccia units have been
mapped in the area. These units have pervasive advanced-argillic alteration, exhibit
tabular to locally irregular geometry, and reach up to 50 m in width. The breccias
postdate the formation of the Au-porphyry mineralization, as suggested by the
presence of mineralized porphyry veinlet clasts within the breccia.
earthy red hematite when close to surface. A close spatial relationship with the abovedescribed breccias units has been indicated.
Gold mineralization is mainly represented by sheeted-vein sets and weak stockwork
networks of quartz veinlets, which show textures similar to those types documented in
other Au-rich porphyry systems in the Maricunga Belt. Au grade in core intersections
with strong banded-veining intensity commonly range from 1.0 g/t to 4.0 g/t. Quartzalunite ledges are discontinuous and volumetrically restricted, and ledge-hosted Au
mineralization at the Property is highly erratic, although it may locally reach up to 2.5
g/t.
On the basis of the weathering state, three main types of mineralization have been
described for the Property: oxide, mixed, and sulphide.
During the 2010 exploration campaign, Orosur drilled 19 DD holes, totalling 3,785 m,
and 11 RC holes, totalling 1,854 m. Industry-standard practices were followed during
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Orosur Mining Inc.
surveying, drilling and sampling during the campaign, and a comprehensive QA/QC
program was in place. ACME Santiago was used as primary laboratory.
AMEC reviewed the exploration methods and verified the data obtained during the AA
and Kinross exploration campaigns prior to the Orosur 2010 drilling campaign. The
available information was partial for the AA and Kinross exploration, and thorough for
the Orosur exploration. As a result of this review, AMEC is of the opinion that:
•
The regional setting and the local geology of the Property are adequately known to
support mineral resource estimation.
•
Surface and down-hole surveying, diamond and RC drilling, logging and sampling
during the 2010 campaign were conducted according to industry-standard
procedures.
•
The sample preparation and assaying procedures during the Kinross and Orosur
exploration campaigns were adequate for this type of deposits.
•
During the Anglo American and Kinross exploration, Au analytical accuracy was
usually within acceptable limits.
•
During the Orosur exploration, sampling and analytical precision for Au and Cu
were within acceptable limits. Analytical accuracy for Au and Cu can be deemed as
acceptable. Cross-contamination for Au and Cu during preparation and assaying
was not significant.
•
Significant Au decay-related or cyclicity-related down-hole contamination did not
occur during the 2010 exploration campaign.
•
Orosur used a proper density determination method, and the amount of
measurements was sufficiently representative of major lithology and mineralization
types.
•
Survey and down-hole survey data, lithology and alteration data, assay and density
data have been accurately recorded.
•
The geological interpretation generally respects the data recorded in the logs and
the sections, as well as the interpretation from adjoining sections, and is consistent
with the known characteristics of this deposit type.
As a result of the review, AMEC is of the opinion that the Pantanillo database can be
used for mineral resource estimation purposes.
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October, 2010
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Orosur Mining Inc.
1.8.2
Resource Estimation
•
The lithology and mineralization, especially the HS ledge breccias, are controls of
gold, copper and arsenic distribution in the deposit. However, the interpreted
models solely were not enough to explain the spatial distribution of relatively higher
grades, therefore, a grade shell at 300 ppb Au had to be used to constrain grade
estimation. Estimation domains are based in the combination of lithology,
mineralization and a three-dimension grade shell model.
•
The spatial analysis show good grade continuity in the orientation of the
mineralized body, correlograms were calculated and model in this direction. Search
orientation was set in the same orientation and ordinary kriging was used for grade
estimation.
•
Validation of the block model shows a good global and local agreement between
the OK estimates and the NN model, and smoothing is controlled.
•
Higher-grade mineralization distribution is well constrained in space within the
deposit, and resulted in the objective definition of volume and grade.
•
AMEC classified the mineral resources in the Measured, Indicated and Inferred
categories based on sample number, data quality, drill-hole density and good
variographic fit.
•
To assess reasonable prospects of economic extraction in open pit operations,
mineral resources were reported within a Lerchs-Grossman (LG)-optimized pit shell
using Whittle® software with the following parameters: gold price of 1,035 US$/oz;
mining cost of 1.65 US$/t; processing cost of 4.0 US$/t; general and administration
cost of 1.0 US$/t, and gold recoveries of 75% for leached and oxide ore types,
•
values.
•
Outside the resource described above, AMEC considers that there is a target for
further exploration of approximately 30 Mt to 40 Mt at a grade of 0.6 g/t to 0.8 g/t
Au of predominantly sulphide mineralization. At this point in time, the potential
tonnage and grade of the exploration target is conceptual in nature, there has been
insufficient exploration to define this target as a mineral resource, and it is
uncertain if further exploration will result in the target being delineated as a mineral
resource.
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October, 2010
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Orosur Mining Inc.
1.9
Recommendations
On the basis of the review and verifications conducted during the preparation of the
Technical Report, AMEC has the following recommendations:
•
The deposit has additional exploration potential for sulphide mineralization in the
deeper horizons. AMEC recommends drilling seven 500 m long drill holes in
sections 3NW, 5NW, 6NW, 7NW, 10NW, 12NW and 16NW (totalling 3,500 m), in
order to delimit the mineralization in depth toward southwest (Table 21-1).
•
AMEC recommends drilling three 500 m deep drill-holes (totalling 1,500 m) in the
south-east portion of the Property, to determine the potential below the ignimbritic
cover (Table 21-1).
•
AMEC recommends drilling six 300 m long infill holes in the high-grade portion of
the deposit to increase the mineral resource classification and to provide
•
AMEC recommends drilling two 500 m long drill holes to test for the presence of
additional porphyry systems on the Property.
•
During future drilling campaigns, the geological QC protocol should be completed
with the insertion of coarse duplicates and fine blanks, and with the submission of
check assays to a secondary laboratory in adequate proportions.
•
In future drilling campaigns, it is recommended that 5% of the RC holes be twinned
by diamond drill holes, including three drill holes from pre-Orosur exploration
campaigns.
•
Orosur should continue to enlarge the density database with new determinations.
•
A new digital topographic surface should be generated to correct the observed
differences between the collar elevations and the current digital topographic
surface.
•
Additional controls of gold distribution, such as a structural control on
mineralization should be investigated and incorporate in future models. The
mineralized body is well constrain spatially but the lithology and mineralization
interpreted models are not enough to explain the occurrence of relatively higher
grades in the deposit.
•
Further investigations should be developed to decrease uncertainty in the recovery
values use in this study to determined reasonable prospects of economic
extraction of mineral resource. A metallurgical test plan, including sampling
protocols, sample representativeness and a test battery regarding the reagents
consumption, metallurgical recovery and other elements that could eventually
Project No. 3107
October, 2010
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Orosur Mining Inc.
decrease the synergies and increment reagents consumption, in particular, cyanide
consumption, recovery, other cyanide consumers and kinetic of the leaching
process, should be analyzed.
•
AMEC anticipates that 8,700 m of drilling will be required in order to accomplish the
above mentioned activities (Table 1-2). This drilling total would be expended
through the 2011-2012 drill seasons. The total budget to complete these activities
is estimated at approximately US$3.5M (Table 1-3).
Table 1-3: Recommended Drilling Program for the Pantanillo Norte Property
Holes
Average Depth
(m)
Delimiting mineralization in depth
7
500
Total
Length
(m)
3,500
Establishing potential under ignimbrites
3
500
1,500
Twin holes on old RC holes
3
300
900
In-fill drilling on high-grade areas
6
300
1,800
2
21
500
1,000
Task
Testing for porphyry-style mineralization
Total
8,700
The budget shown in Table 1-3 should be considered an estimate only, and the actual
costs could vary significantly from this estimate. For this reason, a contingency of 10%
was incorporated into the budget.
Table 1-4: Estimated Budget for the Drill Program and Related Activities for the 20112012 Field Seasons for the Pantanillo Norte Property
Program
Drilling ($200.00/m plus rig mob/demob and supplies)
Laboratory Assays ($40/m)
Geological Supervision and Management (including head office
overhead, travel, accounting, and consultants)
Field Assistants
Field Camp Construction and Supplies (including road maintenance
and equipment, truck rental, kitchen supplies)
Miscellaneous
Sub Total
Contingency (10%)
Total
Cost (US$)
$1,740,000
$348,000
$500,000
$150,000
$300,000
$100,000
$3,138,000
$314,000
$3,452,000
Hydrogeology, environmental and metallurgical studies are currently being carried out
to support a Scoping Study for the project, which is being conducted by AMEC. This
study will help to improve the understanding of the project’s viability.
Project No. 3107
October, 2010
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Orosur Mining Inc.
2.0
INTRODUCTION
2.1
Purpose
On 3 March 2010, Orosur Mining Inc. (Orosur) retained the services of AMEC to
prepare a Technical Report (the Technical Report) covering its Pantanillo Au property
(the Property), located in the III Region, Northern Chile.
This Technical Report discloses an updated mineral resource estimate for the
Property. AMEC understands that this report will be used by Orosur in support of
filings with the TSX Venture Exchange and Canadian provincial securities regulators..
2.2
Qualified Persons
The Qualified Persons responsible for preparation of the Technical Report were Dr.
Armando Simón, P.Geo. (APGO, AIG), Principal Geologist; Paula Larrondo (AusIMM
Member), Principal Geostatistician; and Joyce Maycock, P.Eng. (APEGBC), Project
Manager.
Dr. Simón was responsible for reviewing the regional and property geology,
mineralization, and the available exploration data, and is fully responsible for Sections
1 through 15 and Sections 18 through 23 of the Technical Report related to geology
and exploration procedures. Mrs. Larrondo was responsible for the mineral resource
estimation, and is fully responsible for Section 17 of the Technical Report related to the
mineral resource estimation. Mrs. Joyce Maycock was fully responsible for reviewing
the processing aspects, and is responsible for Section 16 and the portions of Sections
1, 19, 20 and 21 of the Technical Report related to the processing aspects. Each
section of the Technical Report has at least one of the above qualified persons taking
responsibility for preparing or supervising the preparation of the content.
In addition, Dr. Rustin Cabrera reviewed the historic data and exploration, and
conducted the data verification, and Francisco Castillo prepared the resource
estimation, under Mrs. Larrondo’s supervision.
Dr. Simón completed a site visit to the Property on 11 and 12 March 2010. During this
visit, he reviewed the surface geology, as well as surveying, drilling, down-hole
surveying, core logging, sampling, assaying and QA/QC procedures, and sample
security issues during the 2010 drilling campaign. An independent re-sampling
program was conducted as part of AMEC’s QA/QC work to establish the accuracy of
the historic database.
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October, 2010
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Orosur Mining Inc.
2.3
Sources of Information
During the site visit, and later in Santiago, AMEC benefited from the assistance of
various Orosur personnel, mainly Alex Raab, Project Manager. In preparing this report,
AMEC relied on reports, studies, maps, databases and miscellaneous technical papers
listed in Section 23 (References), at the end of this report. Additional information and
data for AMEC’s review and studies were obtained from Orosur on site and in the
Santiago office.
2.4
Terms of Reference
The scope of work included an initial review of the available information and work
procedures, the preparation of the geological model and a resource estimate, and the
preparation of the Technical Report.
AMEC is not an associate or affiliate of Orosur, or of any associated company, or jointventure company related to Orosur. AMEC’s fees for this Technical Report are not
dependent in whole or in part on any prior or future engagement or understanding
resulting from the conclusions of this report. These fees are in accordance with
standard industry fees for work of this nature, and AMEC’s previously provided
estimates are based solely on the approximate time needed to assess the various data
and reach appropriate conclusions.
The effective date of the mineral resource estimmate and this Technical Report is 9
July 2010 which represents the date of the most recent data that informs the resource
estimate and this report. There has been no material change to the scientific and
technical information on the property between the effective date and the date of
signature of the Technical Report.
All measurement units used in this report are metric, and currency is expressed in US
dollars, unless stated otherwise. The currency used in Chile is the Chilean Peso
(CHP). The exchange rate as of 30 July 2010 was US$1.00 equal to CHP$522.363.
3. si2.bcentral.cl/Basededatoseconomicos/951_portada.asp
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3.0
RELIANCE ON OTHER EXPERTS
AMEC has not reviewed the land tenure, nor independently verified the legal status of
Orosur or ownership of the properties or any underlying option agreements. The
information on these matters presented in Sections 4.3- to 4.6 of the report was
supplied by María Consuelo Mengual Henríquez (Carey, 2010a) and Paloma Infante
(Carey 2010b), lawyers and independent experts on mining law and land tenure in
Chile from Carey y Cía.
Project No. 3107
October, 2010
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Orosur Mining Inc.
4.0
PROPERTY DESCRIPTION AND LOCATION
4.1
Location
The Property is located in the Maricunga district, Tierra Amarilla Comuna (borough) III
Region, Northern Chile, 125 km due east of Copiapó, the Region’s capital, at an
altitude of 4,600 m amsl. Copiapó is the centre of a mining district in which various
multinational companies are active in exploration and/or developing mining (Figure 41).
Figure 4-1:
General Location Map (After Siddeley, 2009)
N
50 km
4.2
Property Title in Chile
Chile’s mining policy is based on legal provisions that were enacted as part of the
1980 constitution. These were established to stimulate the development of mining and
to guarantee the property rights of both local and foreign investors. According to the
law, the state owns all mineral resources, but exploration and exploitation of these
resources by private parties is permitted through mining concessions, which are
granted by the courts.
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The concessions have both rights and obligations, as defined by the Constitutional
Organic Law on Mining Concessions (JGRCh, 1982) and the Mining Code (JGRCh,
1983). Concessions can be mortgaged or transferred, and the holder has full
ownership rights and is entitled to obtain the rights of way for exploration and
exploitation. In addition, the concession holder has the right to defend his ownership
against state and third parties. A concession is obtained by a claim application and
includes all minerals that may exist within its area.
During the claim acquisition process, several steps are required (application,
publication, inscription payments, notarization, tax payments, patente payment,
lawyers fees, publication of the extract, etc.) before the application is finally converted
to a declaratory sentence by the court constituting the new mineral property. A full
description of the process is documented in JGRCh (1982, 1983).
Many of the steps involved in establishing the claim are published weekly in Chile’s
official mining bulletin for the appropriate region, and court processes for opposition
from conflicting claims is allowed. Most companies in Chile retain a mining claim
specialist to review the weekly mining bulletins and ensure that their land position is
kept secure.
4.3
Company Ownership, Agreements, and Mining Claims
Orosur Mining Inc., formerly Uruguay Mineral Exploration Inc. (UME)4, is quoted in
Canada (TSX Venture Exchange: OMI) and London (AIM: OMI). The head office is
located at Blanes Viale 6254, C.P. 11.500, Montevideo, Uruguay.
On 8 November 2009, UME and FV signed an agreement to combine their respective
businesses. According to this agreement, UME agreed to acquire all of the issued and
outstanding common shares of FV5.
FV entered into a Staged Purchase Agreement with Anglo American Norte S.A
(AANSA) on 1 October 2009, which entitles FV to the option to purchase the group of
mining concessions (concesiones de explotación) covering the Property (Table 4-1;
Figure 4-2)
Pursuant to the Stage Purchase Agreement, FV is obliged to pay AANSA a total of
US$850,000 and to complete minimum expenditures and drilling according to the
schedule presented in Table 4-2.
4. The UME Corporate name was modified to Orusur Mining Inc. On 7 January 2010 as per Certificate of
Ammendment. Issued b y Yukon Community Services.
5. www.orosur.ca/news/index.php?&content_id=67
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Orosur Mining Inc.
Table 4-1:
AANSA Mining Properties Granted in Option or Promise to Purchase to FV
(Carey, 2010a)
Name
Nr. of
Claims
Type of
Concession
Cecilia 1 to 950
Gabriela 1 to 1000
Guillermo Antonio 1 to 400
950
1,000
400
Mining
Mining
Mining
Table 4-2:
Current
Registration
Page
Nr.
Year
964
249
2009
965
250
2009
966
251
2009
Custody
Office
Surface
(ha)
Copiapó
Copiapó
Copiapó
4,750
5,000
2,000
Schedule of Payments and Minimum Expenditures (Carey, 2010a)
Purchase
Considerations
Cash deposit
Option Payments
Option Payments
Sale Price
Total
Date
1-Oct-2009
1-Oct-2010
1-Oct-2011
1-Oct-2012
Option
Payments
US$ 100,000
US$ 150,000
US$ 300,000
US$ 300,000
Minimum
Expenditure
US$ 500,000
US$ 1,500,000
US$ 2,000,000
Minimum Drilling
(m)
1,500
Additional 5,000
Additional 6,000
US$ 850,000
US$ 4,000,000
12,500
Notes
1
2
3
Notes
Minimum Conditions in addition to Option Payments
1. Subject to minimum US$500,000 expenditure and 1,500 m drilling
2. Subject to minimum US$1,500,00 expenditure and additional 5,000 m drilling
3. Subject to minimum US$2,000,00 expenditure and additional 6,000 m drilling
NSR Conditions
1. NSR. 3.5% or US$300,000 per year for period 2013 to 2015
2. NSR is minimum of US$ 1 million per year from 2015 onwards
According to Carey (2010a), the above-mentioned Staged Purchase Agreement is not
affected by the payment of royalties or other types of obligations in favour of third
parties, except for the minimum payments and conditions established on the above
mentioned schedule (Table 4-2). Carey (2010a) also stated that FV has complied with
all payments and obligations due by the date (30 July 2010) with respect to AA arising
from the Staged Purchase Agreement. In addition, FV foresees that it will be able to
pay in due time and form the next instalment of USD$150,000 to AANSA by the due
date on 1 October 2010.
AMEC has fully relied on the information on this subject provided by María Consuelo
Mengual Henríquez as listed in the Reference section (Carey, 2010a).
Project No. 3107
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Figure 4-2:
4.4
Summary Land Tenure Map (Carey, 2010a)
Surface Rights
FV currently does not have any surface land rights in the Pantanillo Norte project area
(Carey, 2010a). However, in accordance with the Chilean Mining Code, any titleholder
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Orosur Mining Inc.
of a mining concession, whether for exploration or exploitation, would have the right to
judicially impose an easement over the surface land as required for the convenient and
comfortable exploration or exploitation of his/her concession. Accordingly, and as
general rule, in the event that the surface property owner is not agreeable to grant the
easement voluntarily, the titleholder of the mining concession may request said
easement before the ordinary courts who shall grant it upon determination of the
compensation for losses as deemed fit.
4.5
Water Rights
According to Carey (2010a), FV is currently carrying out exploration studies aimed to
discover and extract underground waters for Pantanillo project. There is a pending
exploration license request at the Regional Water Bureau covering 4,023 ha. If
granted, the exploration licence would provide an exclusive right to explore and
discover the existence of unknown underground sources of water in the area, with a
legal preference for the granting of water rights on the discovered sources, if any.
Additionally, FV has requested a survey of existing underground water rights owned by
third parties located within a given area of interest for the Pantanillo Norte project.
4.6
Environmental and Socio-Economic Issues
The following summary is based upon Chile’s Environmental Law and the regulations
regarding environmental impact studies, as posted on the web site of Chile’s Regional
Commission for the Environment (CONAMA)6.
All mining projects to be executed in Chile have to comply with environmental
regulations defined in Law Nº 19,300 (CONAMA, 1994), which came into force in
March 1994, and was modified in January 2010.
Currently, there are two ways of submitting a project for environmental approval, which
depend on the potential environmental impacts. If the project will not generate
significant impacts, the law only requires that an Environmental Impact Statement
(DIA) be prepared; otherwise, an Environmental Impact Study (EIA) is necessary. The
latter includes baseline studies, a complete technical description of the project, impact
assessment, public hearings and environmental plans, among others.
Mining projects are generally supported by an EIA, except for exploration activities not
located in wildlife conservation areas. The definition of exploration in the context of this
regulation is “actions or works leading to the discovery, characterization, delimitation
6. www.conama.cl
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and estimation of the potential of a concentration of mineral substances which may
eventually lead to a mine development project.”
The EIA and DIA are submitted to the review of the public authority, which will take
120 days and 60 days, respectively, for the approval or rejection the project. If the
project is approved, an environmental permit is awarded and the development can
commence. Usually, the approval process needs additional time to resolve the most
critical questions from stakeholders.
According to Julian Ford (personal communication, 2010), FV is currently applying for
a DIA to allow for the further drilling of the project, following the anticipated publication
of the first resource at Pantanillo Norte by FV.
The Property is located within the Pantanillo Biologic Corridor, a Priority Site for
Biodiversity Conservation (Carey, 2010b). These sites are not environmentally
protected areas, but sites where conservation is regarded as a process of integration
of sustainable productive practices with biodiversity conservation7. The Property is also
situated 2.5 km from the Nevado Tres Cruces National Park, an environmentally
protected area8, and 1 km from the Laguna del Negro Francisco and Laguna Santa
Rosa Lacustrine Complex, a RAMSAR site9 (Carey, 2010b).
7. www.conama.cl/portal/1301/article-44669.html
8. www.conaf.cl/parques/ficha-parque_nacional_nevado_de_tres_cruces-10.html
9. www.wetlands.org/RSIS/_COP9Directory/Directory/ris/6CL006es_part1.pdf
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5.0
ACCESSIBILITY, CLIMATE, LOCAL RESOURCES,
INFRASTRUCTURE AND PHYSIOGRAPHY
5.1
Accessibility
The Property is located in the III Region, Northern Chile, approximately 700 km northnortheast of Santiago, and 120 km east of Copiapó, the regional capital and the
closest major center (about 125,000 in 2002; Figure 4-1). The Property extends
approximately between 26° 36' S and 27° 31' S, and between 68° 54' W and 69° 17'
W, and the altitude ranges between 4,440 m and 4,680 m amsl. The approximate UTM
coordinates (Zone 19J, datum WGS-84) of the center of the property are 492,400E /
6,965,200N. The magnetic declination on 31 July 2010 was 2° 9' west, with 0° 10'
counter-clockwise yearly variation10.
Good road communication exists along Highway 5 between Copiapó and Santiago
(801 km), La Serena (333 km) and Antofagasta (566 km). LAN, SkyAirlnes and other
companies service various daily flights between Copiapó and Santiago, Antofagasta,
Calama and La Serena.
Access to Pantanillo from Copiapó is along the international road CH-31, which links
Copiapó to Fiambalá, in Argentina. The initial 30 km of the route is on a paved
highway; the remainder is a graded gravel road in fair condition. The total driving time
is about 3.5 hours. A 4-wheel drive vehicle is recommended for driving around the
Property and for several portions of the final segments of the access road. Some
portions of the road may be impassable during or immediately after periods of heavy
snowfall.
Copiapó has excellent infrastructure, including power supply and airport facilities,
health and banking services, modern communication facilities, hotel accommodation,
general stores, schools and colleges, etc. Experienced mining personnel, including
skilled workers and qualified professionals, are available at Copiapó, Santiago, La
Serena and Antofagasta.
5.2
Physiography, Climate, Vegetation and Fauna
This information was mainly extracted from Siddeley (2009). The physiography of the
Maricunga area is extremely rugged, of volcanic origin and immature topography,
separated by wide flat valleys and salars, and underlain by thick ash-fall deposits.
10 www.gabrielortiz.com
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Bright, pastel-coloured, hydrothermally-altered patches of volcanic terrain mark the
centres of economic interest.
The Property is dominated by the N-S-trending mountain ranges of the Sierra de la Sal
on the west, and Sierra Colorada on the east, reaching altitudes of over 4,825 m amsl.
The Cerro Azufre volcano (Co. Copiapó), located just 15 km north of the project,
reaches 6,052 m amsl.
The climate at the area surrounding the saline Santa Rosa and Negro Francisco lakes
and the Salar de Maricunga, where the Property is located, is of the cold-mountaindesert climate type. This climate is characterized by very dry air, large seasonal and
daily temperature differences, with extremely cold nights. During the winter major
snowfalls are recorded, and the snow may stay on the mountain slopes even until the
spring (CONAF, 1997). Exploration work is usually restricted to late spring (October) to
early autumn (April).
At Pantanillo, 4,300 m to 4,700 m above sea level, the desert temperatures at night
drop to freezing point or below throughout the year (averaging minus 6°C). The
summer average during the day is 18°C. There are a few streams originating from the
mountains that drain into the closed topographic basin, surrounded on all sides by
rugged volcanic terrain.
Copiapó has a Mediterranean-type, warm, dry desert climate, with the Copiapó river
providing the only irrigation for the local farming and water for the city. As one climbs
the Andean foothills to the east, the temperatures become extreme. The typical
exploration season is between November and April, with sporadic winter storms
starting in April which could disrupt transport to the site even if snow cover is not
usually deep. Camp sites at these altitudes need considerable protection against
freezing temperatures, and inevitable cuts in communication and provisions may
occur.
Given the remoteness and the harsh cold-desert climate, there are no permanent
settlements and cultivation. Guanacos (Lama guanicoe) and vicuñas (Vicugna
vicugna) roam free in small herds, feeding on the meagre vegetation along valleys and
lake-edges. Certain flamingo species can be found at the salar lakes, as
Phoenicopterus chilensis, Phoenicoparrus andinus and Phoenicoparrus jamesi.
5.3
Local Resources and Infrastructure
The Laguna Santa Rosa - Salar de Maricunga sector has been used since the time of
the Inca culture for crossing the cordillera to-and- from Argentina, and wetlands along
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the valleys, with scarce grassy vegetation, were used to feed cattle during the summer
times or during the expeditions between Chile and Argentina.
Exploration and mining have been the main activities in the region for decades, but
particularly during the last ten to fifteen years, when numerous exploration and mining
camps were established. In particular, the Maricunga (ex-Refugio) mine has been
active since 1996. In spite of the fact that international traffic is not intense, there is a
Chilean customs/border control office with excellent facilities on the border with
Argentina.
A small but permanent stream runs along the valley and is suitable for camp use. A
drilled water well (cased and locked) exists near the old campsite. Kinross also pumps
well water in the main valley within the Pantanillo concessions for use at Refugio, its
mine to the south. Power for pumping and for the mine, is supplied by a high-voltage
electric line (750 KW; 23,000 V) extended north from Maricunga as far as Pantanillo
(Siddeley, 2009).
5.4
An Overview of Chile
5.4.1
Introduction
Chile is unique, given its very long (4,345 km) and comparatively narrow shape
(ranging from 90 km width in the south to 380 km width in the north, with 177 km
average width), and for its great variety of natural features. The country extends from
18°S to 56°S latitude, and contains one of the driest regions in the world, as well as
one of the wettest areas in South America. Chile is bounded on the north by Peru, on
the northeast by Bolivia, on its long eastern border by Argentina and on the west by
the Pacific Ocean (Figure 5-1). The country covers an area of approximately 756,000
km2 and has a population of approximately 16.9 million people.
5.4.2
Geography
Chile consists of three distinct longitudinal structural regions: the Andes, the Coastal
Range and the Central Valley, each with its own diverse climatic regions11.
The Andes
The Andes (Andean Cordillera) run along the entire length of the eastern part of the
country. The watershed between the Pacific and Atlantic oceans, which follows the
central and often highest ridges of the Andes, was adopted (by agreement with
11. www.turistel.cl
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Argentina) as Chile's eastern boundary. The Chilean Andes are highest, most rugged
and precipitous in the northern and central parts of the country, with peaks above
6,000 m amsl, including South America's highest peak, Aconcagua (6,960 m amsl)
which is close to Santiago. Mountain passes in this part of the Andes are few and
difficult, and generally rise above 3,000 m amsl. South of Santiago, the Andes
become gradually lower, with peaks of approximately 3,700 m amsl. The passes are
correspondingly much lower and easier to negotiate. In the extreme south, the Andes
are fragmented by deep glacial valleys, ocean inlets and channels. The mountains
extend through the island of Tierra del Fuego to the southern end of the continent.
Figure 5-1:
Map of Chile
N
Pantanillo
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In the north, at the latitude of Antofagasta, the Chilean Andes consist of two almost
parallel ranges: the western Domeyko Cordillera and the eastern Andean Cordillera
divided by the Andean Depression.
Near the Chilean Andes and along their eastern flank is one of the world's densest
concentrations of volcanoes, both extinct and active. There are over 2,000 volcanoes,
including 48 that have erupted at least once within the last 100 years. The abundance
of volcanic features in Chile and its vicinity is also reflected in the frequent seismic
events and conspicuous evidence of recent tectonic movements.
The Coastal Range
The second structural region is the Coastal Range (Cordillera de la Costa), which
follows the coastline closely throughout northern and central Chile, from Arica to
Puerto Montt. The Coastal Range rises abruptly from the shoreline in high cliffs that
form an unbroken wall for hundreds of kilometres, creating a coastline devoid of
natural harbours and a formidable obstacle to access inland. Large parts of the
coastal range are actually an eroded plateau descending west to the sea by cliff-bound
terraces. The coastal range rises to an elevation of approximately 2,700 m amsl. The
southward extension of the coastal range beyond Puerto Montt forms a chain of
approximately 3,000 hilly islands, extending along a fjord-lined coast to Cape Horn at
the southern extremity of the South American continent. The largest of these islands
is Chiloe, just south of Puerto Montt.
The Central Valley
The third structural region, and the most important one, insofar as human settlement is
concerned, is the depression between the Andes and the Coastal Range, known as
the Central Valley. This feature is a long and narrow basin of varying width, reaching
approximately 80 km at its widest section. The Central Valley is not continuous, as it is
interrupted by east-west oriented spurs from the Andes, and is divided by a wide
mountainous intrusion into two main basins, each of which includes a number of
smaller basins.
The northern basin, extending from Arica to Copiapó, includes the Atacama Desert.
The second major basin is that of central Chile, extending from Santiago southward to
Puerto Montt, and is Chile's main agricultural area. This basin is also Chile’s most
densely inhabited region, and includes the country’s three largest metropolitan areas:
Santiago, Valparaíso/Viña del Mar and Concepción. It is climatically the most
attractive part of the country.
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The Loa is Chile's longest river, at about 483 km long, and other principal rivers
include the Aconcagua, Baker, Bío-Bío, Imperial, Maipo, Maule, Palena, Toltén and
Valdivia Rivers.
5.4.3
Climate
Extending over 38° of latitude, and from sea level to altitudes of nearly 7,000 m amsl,
Chile has a wide variety of climatic conditions. Extremely arid conditions prevail over
the northern part of the country in the Atacama Desert, where the average annual
rainfall is approximately 1 mm. Temperatures are moderate along the coast
throughout the year and more extreme inland, especially in the Central Valley.
Central Chile (30°S to 40°S latitude) has a Mediterranean-type climate, with cool and
rainy winters (April to September) but without a completely dry season. Average
annual precipitation increases substantially and temperatures decrease toward the
south. The average temperatures for the hottest (January) and coldest (July) months
at Santiago are 20°C and 8°C, respectively. The average annual precipitation at
Santiago is approximately 380 mm.
The climate of the southern region is cool and rainy throughout the year, and is
characterized by abundant low clouds. The average temperatures for the warmest
(January) and the coldest (July) months are 14°C and 4°C, respectively. The average
annual precipitation is 3,022 mm. The changes of the snow line on the westwardfacing slopes of the Andes can serve as an indication of the variation in climatic
conditions with latitude and elevation. The line of permanent snow is approximately
5,500 m amsl in Chile's extreme north. It descends to about 4,300 m amsl at the
latitude of Santiago and to 670 m amsl at Tierra del Fuego.
Due to its location in the southern hemisphere, the main seasons in Chile are: spring September 21 to December 20; summer - December 21 to March 20; autumn - March
21 to June 20; and winter – June 21 to September 20.
5.4.4
Demography
Chile’s population currently stands at approximately 16.9 million with a 0.97% average
annual population growth rate12. The birth rate in 2010 was estimated to be 14.46
births/1,000, while the death rate was 5.9 deaths/1,000 (CIA, 2010). Chile is one of
the most urbanized countries in Latin America, with 88% of the population residing in
urban areas. Nearly 90% of the population is concentrated in central Chile, in the area
between Coquimbo in the north and Puerto Montt in the south, mainly in the region's
12. en.wikipedia.org/wiki/Demographics_of_Chile
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Central Valley. Even in this part of the country, with the exception of the Santiago
metropolitan area, the average population density does not exceed 50 inhabitants per
square kilometer. The average population density for the entire country is 18
inhabitants per square kilometer. The largest cities in Chile include Santiago,
Valparaiso/Viña del Mar, Concepcion, Antofagasta, Puerto Montt, La Serena and
Copiapó.
The official language in Chile is Spanish; however, some of the indigenous populations
still use native languages, mainly mapudungún, the Mapuche dialect. The majority of
the Chilean people come from a mixed ethnic background of European and Native
American ancestry. In the decades following World War II, immigration from Europe
contributed much to the comparatively rapid growth of the population. The largest
ethnic groups in Chile include: white and white-Amerindian, 95.4%; Mapuche, 4%;
other indigenous groups, 0.2%. The main Native American indigenous communities
include: Mapuche (also called Araucanian), Aymara, Rapa Nui, Quechua, Colla,
Alacalufe and Yagán. These communities are mainly concentrated in the Andes in
northern Chile, in some valleys of south-central Chile, and along the southern coast.
In 1966, reforms to the education system changed the length of primary education to
eight years and secondary education to four years. In 2004, the adult literacy rate was
estimated at 95.7%, with school life expectancy of 14 years (CIA, 2010).
Over the past 15 or 20 years, heavy investments in programs for very poor and in
water and sanitation systems helped lower infant mortality rates and raise life
expectancy. In 2003, life expectancy was estimated at about 77.5 years, while infant
mortality was estimated at 7.5 deaths per 1,000 live births (CIA, 2010).
The religious background of the majority of Chileans is Roman Catholic (70%), while
about 17.2% are Evangelical or Protestant. The remainder is made up of agnostics
and other smaller religious groups, which include Jewish, Muslim and Christian
Orthodox.
5.4.5
Political
In 1973, Chile’s three-year-old Marxist government was overthrown by a dictatorial
military regime led by Augusto Pinochet, who ruled until a freely-elected president,
Patricio Aylwin, took office in 1990. Sound economic policies, first implemented by the
Pinochet dictatorship, led to unprecedented growth in 1991 to 1997 and have helped
secure the country's commitment to democratic and representative government.
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Chile’s current chief of state and head of government is President Sebastián Piñera,
who was elected on 15 January 2010. Presidential elections take place every four
years.
5.4.6
Economy and Business Investment Climate
The following summary on Chile’s economy is taken directly from the CIA factbook
(CIA, 2010).
Chile has a market-oriented economy characterized by a high level of foreign trade
and a reputation for strong financial institutions and sound policy that have given it the
strongest sovereign bond rating in South America. Exports account for more than onefourth of GDP, with commodities making up some three-quarters of total exports.
Copper alone provides one-third of government revenue. During the early 1990s,
Chile's reputation as a role model for economic reform was strengthened when the
democratic government of Patricio AYLWIN - which took over from the military in 1990
- deepened the economic reform initiated by the military government. Growth in real
GDP averaged 8% during 1991-97, but fell to half that level in 1998 because of tight
monetary policies implemented to keep the current account deficit in check and
because of lower export earnings - the latter a product of the global financial crisis. A
severe drought exacerbated the situation in 1999, reducing crop yields and causing
hydroelectric shortfalls and electricity rationing, and Chile experienced negative
economic growth for the first time in more than 15 years. In the years since then,
growth has averaged 4% per year. Chile deepened its longstanding commitment to
trade liberalization with the signing of a free trade agreement with the US, which took
effect on 1 January 2004. Chile claims to have more bilateral or regional trade
agreements than any other country. It has 57 such agreements (not all of them full free
trade agreements), including with the European Union, Mercosur, China, India, South
Korea, and Mexico. Over the past five years, foreign direct investment inflows have
quadrupled to some $17 billion in 2008, but FDI dropped to about $7 billion in 2009 in
the face of diminished investment throughout the world. The Chilean government
conducts a rule-based countercyclical fiscal policy, accumulating surpluses in
sovereign wealth funds during periods of high copper prices and economic growth, and
allowing deficit spending only during periods of low copper prices and growth. As of
September 2008, those sovereign wealth funds - kept mostly outside the country and
separate from Central Bank reserves - amounted to more than $20 billion. Chile used
$4 billion from this fund to finance a fiscal stimulus package to fend off recession. The
economy was starting to show signs of a rebound in the fourth quarter, 2009, although
GDP still fell more than 1% for the year. In December 2009, the OECD invited Chile to
become a full member, after a two year period of compliance with organization
mandates. The magnitude 8.8 earthquake that struck Chile in February 2010 was one
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of the top ten strongest earthquakes on record. It caused considerable damage near
the epicenter, located about 70 miles from Concepcion - and about 200 miles
southwest of Santiago.
Most of Chile’s foreign investment comes from the U.S.A., Canada and Spain, and is
expended on the mining industry along with substantial amounts also on the electricity
and service industries. Chile's economy is primarily based on its rich mineral
resources, agriculture, fishing grounds and on industry. Mining plays a dominant role
in northern and central Chile, while forestry, fishing and agriculture are important in the
south. Chile’s main exports are minerals, fishmeal, fruits, wood pulp and paper, and
chemicals. Mining contributes nearly half of total exports. The GDP estimate for 2009
was US$243.7 billion (purchase power parity), of which 5.6% corresponded to
agriculture, 34.5% to industry and 51.9% to services. The public debt amounted 6.1%
of the GDP (CIA, 2010).
The exploitation of Chile's mineral resources is to a large extent in the hands of foreign
companies, but Chilean nationalized companies, such as Codelco and CMP, are
considered major world producers of copper and iron, respectively.
The small miner (pirquinero) has played an important role in Chilean mining history,
even though today their production represents only a small fraction of the total annual
production in Chile. Thousands of pirquinero operations still exist throughout the
country, many of which receive a subsidized copper price at the government-run
Empresa Nacional de Minería (ENAMI) flotation and heap leach plants. Most of these
operations are exploiting narrow, high-grade veins and/or mantos, using crude,
inefficient mining and milling methods; health and safety measures are rarely
considered. In addition, high-grade dumps at abandoned mining operations are often
scavenged by the pirquineros, who selectively hand-sort the dumps and haul them to
be processed. A limited number of small operations are using more advanced
technology and processing their own mined material by heap leach or vat leach
methods, or with sulphide flotation plants.
5.4.7
Mineral Resource Data
Over the last 20 years, new geologic data in Chile have been generated at an
increasingly rapid pace by state agencies, universities and private industry. This
progress is largely driven by governmental mapping and industry mineral exploration
programs. New digital geological, lithotectonic, geophysical and hydrogeological maps
are constantly being produced by the Chilean state geological agency
SERNAGEOMIN and a project started in 1999, the Multinational Andean Project
(MAP). MAP is the result of collaboration between the Canadian International
Development Agency, the Geological Survey of Canada and the National Geoscience
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Agencies of Chile, plus Argentina, Bolivia and Peru, which will continue to help in the
understanding of the metallogeny of Chile (and other parts of South America) and
assist in the future development of mineral resources.
5.4.8
Chilean Mining
The Chilean mining sector has grown rapidly since the late 1970s with the start-up of
numerous new world-class mining operations. The Chilean mining sector is attractive
to both national and foreign investors. Chile is still considered to be one of the most
favourable South American countries for foreign investment. As a result of Chile’s
large and active mining industry, the country is well-positioned to meet infrastructure
and labour demands for new mining projects. The estimated mining investment
between 2008 and 2018 totals US$40,000, of which US$12,000 will correspond to
Codelco, and US$28,000 to the private sector13.
Mining represented 6.7% of the GDP14, and generated exports of US$40,250 billion in
2008 (59% of total exports)15. The bulk of Chilean mining is concentrated in the
northern desert areas. Chile is the largest copper producer and exporter in the world,
and hosts roughly 30% of the world’s reserves.
State-owned Codelco remains the country’s largest copper producer, with production
totalling 1.7 Mt, or approximately 32% of Chile’s copper output in 200910. The rest of
the copper production (3.7 Mt, or 68% of the total output) was produced by the private
industry, mainly by Escondida (1,104 kt), Collahuasi (536 kt), Los Pelambres (323 kt),
Anglo American (429 kt), El Abra (164 kt), Candelaria (134 kt) and Zaldivar (137 kt).
Chile is also an important gold, molybdenum, silver and iron ore producer. Output
figures for selected metals are presented in Table 5-1.
13. www.sonami.cl/pdf/memoria_2008_2009.pdf
14. www.cochilco.cl/productos/anuario.asp
15. www.sonami.cl/pdf/memoria_2008_2009.pdf
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Table 5-1:
Chilean Metallic Production – 2002 to 2009 (selected commodities)
Commodity
Production
2005
2006
2002
2003
2004
2007
2008
2009
Copper (kt Cu)
4,580.6
4,904.2
5,412.5
5,320.5
5,360.8
5,557.0
5,327.6
5,389.6
Gold (kg Au)
38,687.9
38,953.6
39,985.7
40,447.0
42,100.0
41,527.0
39,162.0
40,834.0
Molybdenum (t Mo)
29,466.4
33,373.8
41,883.2
48,040.7
43,277.6
44,912.1
33,686.5
34,924.9
Lead (t Pb)
2,895.0
1,697.0
2,286.0
878.0
672.0
1,305.0
3,985.0
1,511.0
Zinc (t Zn)
36,161.0
33,051.0
27,635.0
28,841.0
36,238.0
36,453.0
40,519.0
27,801.0
Iron (kt iron ore)
7,268.8
8,011.0
8,003.5
7,862.1
8,628.2
8,817.7
9,315.6
8,242.3
Silver (kt Ag)
1,210.5
1,312.8
1,360.1
1,399.5
1,607.2
1,936.5
1,405.0
1,301.0
Source: www.portalsonami.cl
Non-metallic mining in Chile involves a wide range of commodities. The main nonmetallic products are calcium carbonate, gypsum, iodine, lithium carbonate, nitrates,
quartz, sodium chlorides and ulexite. Chile is the largest iodine producer in the world.
5.4.9
Mineral Royalty Law
In 2005, during the last year of President Ricardo Lagos' government, the Chilean
congress passed Law 20,026 (Royalty II), a tax on operating income derived from the
sale of mineral products, both metallic and non-metallic (MEFR, 2005). The law
established a sliding tax, depending on the value of total sales measured in copper
equivalent, ranging from 0.5% (for sales exceeding the value of 12,000 t Cu) to 5% (for
sales exceeding the value of 50,000 t Cu). The law allows for 50% of the royalties to
be offset against corporate tax during 2006 and 2007.
Companies with new investments of US$50 million or more have the option of signing
a 15-year tax-stability pact with the state, which will include the new sector-specific tax.
Companies with current mining investments protected under Chile's DL 600 foreign
investment law (MEFR, 1993) have the option of waiting for their DL 600 contracts to
expire, after which time their investments will be subject to the 5% mining tax.
However, if these companies choose to renounce their DL 600 status, they will face a
4% mining tax during the next 12 years, and keep the benefits of accelerated
depreciation until the end of 2007, as well as a tax-stability clause.
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6.0
HISTORY
The exploration history of the Property was summarized by Siddeley (2009). No
reports are available from the initial exploration conducted during the 1970’s by
Anaconda, the original holder of the concessions. After the discovery of the El Indio
bonanza-style gold deposit, the Maricunga area received increased attention from
exploration and mining companies, and low-level color anomalies, readily identified in
air photos, became new exploration targets for gold.
Empresa Minera Mantos Blancos (EMMB), a Chilean subsidiary of Anglo American
(AA), acquired the Pantanillo concessions in 1983, and explored the area intermittently
through the 1990’s. Nevertheless, in spite of the considerable efforts, new El Indio
bonanza-style mineralization was not identified. Instead, low-grade, high-volume, AuCu porphyry-style mineralization was discovered in different prospects, becoming a
characteristic signature of the Maricunga region.
As a result of AA’s and Cominco’s joined work during the 1980’s, many such prospects
were explored, among them Aldebarán, Marte-Lobo, Pantanillo, etc. In 1997, EMMB
completed a resource estimation on a gold deposit in the Pantanillo Norte prospect
(Siddeley, 2009). In middle 2000’s Kinross optioned the Property from AA, and
conducted soil and rock geochemical surveys, geological mapping and trenching over
40 km2.
From 1987 to 2008, in distinct periods, AA, EMMB and Kinross drilled a total of 7,879
m (30 holes) reverse circulation (RC), 6,743 m (17 holes) diamond drilling (DD) and
700 m (one hole) combined RC/DD in the Pantanillo Norte prospect. With these data,
Kinross estimated in 2007 a gold resource estimate (Siddeley, 2009). In addition, five
holes totalling 1,363 m were drilled in the Quebrada Pantanillo prospect (not included
in this report).
During early 2010, following the merger between UME and FV, Orosur conducted a
drilling program totalling 3,785 m in 19 DD holes and 1,854 m in 11 RC holes. This
report includes a new NI 43-101-compliant resource estimated based on the AA,
Kinross and Orosur drilling, and is planning to complete a scoping study by the end of
2010.
No formal historical production has been reported in the area, although isolated
pirquineros have mined from time to time certain outcropping silica “ledges” that may
contain gold values exceeding 5 g/t, and who used to gather the more attractive
material for processing in Tierra Amarilla and Copiapó at local artisan facilities
provided with “trapiches”, which use mercury-coated copper plates to collect the gold
particles freed during crushing.
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7.0
GEOLOGICAL SETTING
7.1
Introduction
The information presented here in has been extracted from internal and public reports,
quoted in the following text and referenced in Section 21, and complemented with
information provided by Orosur geologists.
7.2
Regional Geology and Tectonic Evolution
7.2.1
Regional Geology
The following description mainly consists of excerpts from Muntean and Einaudi
(2001), Callan (2006), Siddeley (2009) and Raab (2010).
The Maricunga belt represents a 200 km long by 50 km wide metallogenic district,
located along a NNE-SSW-trending chain of Upper-Oligocene to Mid-Miocene age
andesitic to dacitic volcanoes running along the Argentine-Chile border. The volcanoplutonic arc developed on a Pennsylvanian to Triassic basement composed of
granitoids and intermediate to silicic volcanic rocks, overlain by Mesozoic to early
Tertiary continental volcanic and clastic rocks. Subsequent erosion of late Tertiary
volcanoes exposed the frequently hydrothermally altered sub-volcanic porphyry stocks
(Muntean and Einaudi, 2001; Figure 7-1).
The overall geological setting of the Maricunga belt corresponds to compounded, interfingering, discontinuous and texturally highly variable strato-volcanic accumulations.
Although active volcanism is present in Northern and Southern Chile, there is no
recent volcanic activity in the Maricunga belt.
The Astaburuaga formation is the oldest exposed volcanic formation in the Pantanillo
area, and has been dated by SERNAGEOMIN at 30 Ma to 35 Ma (whole rock
analysis), or mid-Tertiary (Oligocene). Meanwhile, Sillitoe reported a 22 Ma date for
hypogene alunite from a late-hydrothermal phase, which is similar to dates obtained
from hydrothermally mineralized areas at Refugio, La Pepa and La Coipa. Even
younger dates (9 Ma to 13 Ma) have been reported from mineralized areas at Marte
and Aldebarán, indicating that the magmatic and hydrothermal evolution spanned
several million years throughout the Maricunga belt.
The strongly disturbed and evidently explosive nature of the overlapping tuffs,
breccias, agglomerates and ash-falls of the several volcanic centers, the presence of
outcropping intrusive bodies of andesitic to dacitic composition and the extensive
hydrothermal alteration make regional stratigraphic correlation a very difficult task.
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The Property is located in the central part of the Maricunga Belt, directly between the
Maricunga Mine (Ex-Refugio) and the Marte-Lobo project, both owned and operated
by Kinross. The Maricunga Belt hosts numerous Au and Au-Cu porphyry-style deposits
(i.e., Refugio, Cerro Casale, La Pepa, Marte, Lobo), related high-sulphidation
epithermal deposits (La Coipa), and bonanza-type vein deposits (La Pepa), associated
with the late Tertiary andesitic to dacitic volcanism and local litho-cap development.
Figure 7-1:
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Schematic Geologic Map of the Maricunga Belt (Source: Davidson and
Mpodozis, 1991, quoted by Muntean and Einaudi, 2001).
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The regional structural setting of the Maricunga Belt includes:
7.2.2
•
N/NE-trending high angle reverse faults which bound basement rocks
•
NW-striking normal faults with SW/NE extension components
•
E/NE lineaments, interpreted as dextral shear zones.
Tectonic Evolution
Barra et al. (2002) synthesized the tectonic evolution of the Northern Chile continental
margin, which is explained in the following paragraphs. The first phase of the
Gondwanian tectonic cycle consisted of Late Carboniferous oceanic subduction.
Felsic magmatism associated with this event is represented by the Choiyoi Group of
the Cordillera Frontal in Chile and Argentina.
Subduction practically ceased (or was very slow) between the Late Permian and Early
Jurassic, and short-lived back-arc and rift basins developed in the eastern side of the
magmatic arc (i.e., Cuyo basin). Felsic magmatism is interpreted to be the result of an
early cycle of subduction followed by acid, non-orogenic magmatism associated with
active extensional faulting.
An accretionary prism was formed in this period along the western continental margin,
forming the basement of the Coastal Cordillera, although most of this accretionary
prism was later removed by tectonic erosion.
Subduction recommenced in the Jurassic, resulting in the development of the La
Negra magmatic arc, which extends from Arica to Chanaral. The poorly evolved,
mantle-derived magmatism of La Negra Formation was followed by the emplacement
of the Coastal Batholith granitoids during the Jurassic and Early Cretaceous. Oblique
subduction, parallel to the paleo-trench, was responsible for the Early Cretaceous
development of the 1,000 km long Atacama strike-slip fault, which affected the Coastal
Cordillera. The volcanic activity migrated eastward. Terrane accretion did not occur.
Complex basins (fore-arc, intra-arc and back-arc types) developed in the Andes during
that period. Basin subsidence was controlled by extensional tectonics. A Late Triassic
marine transgression formed a small basin at the site of the present Domeyko
Cordillera. Marine conditions were maintained until Tithonian-Neocomian time, when
evaporate sequences marked the end of marine deposition (Arcuri and Brimhall,
2002). During the Early Cretaceous, the basin was filled with continental red bed
sediments and lava flows from the La Negra magmatic arc (Aeropuerto Formation).
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In the Middle Cretaceous (105 Ma), the La Negra magmatic activity ceased, and the
Domeyko Proto-Cordillera (DPC) was formed as a consequence of basin closure and
uplift. Volcanism resumed in Late Cretaceous, with the continuous eastward migration
of the magmatic arc.
Although volcanism decreased in Oligocene, intrusive activity was widespread and
important during Late Eocene and Oligocene (48 Ma to 28 Ma). Most of the worldclass Chilean porphyry copper deposits were emplaced during this period along the
axis of the DPC and through strike-slip faults, such as the West Fissure in
Chuquicamata, connected to highly oblique convergence of the Nazca plate.
The lack of current volcanic activity in the central section of the Andean cordilliera
(28°S to 33°S) is explained by a strong reduction of the subduction angle of the Nazca
Plate, which is associated by many authors to the subduction on that region of the
Juan Fernández dorsal, much lighter as compared to the enclosing oceanic crust.
Flattening of the subducting slab began in the middle Miocene (18 Ma) and resulted in
basement uplift and the continuous eastward migration of the volcanic arc in the late
Miocene to early Pliocene (Muntean and Einaudi, 2001). The subhorizontal subducted
slab reaches 400 km width at the 32°S (Tassara y Yáñez, 2003).
7.3
Local Geology
7.3.1
Stratigraphy and Magmatism
The Property geology description has been summarized from Callan (2006), Siddeley
(2009) and Raab (2010).
The Property lies on the eastern flanks of the Azufre/ Copiapó volcanic complex, within
a mainly dacitic to locally rhyolitic in composition, hydrothermally altered volcaniclastic
sequence, with an estimated thickness exceeding 2,000 m, showing sub-horizontal to
shallow N or E dips. Callan (2006) described the pre- to syn-mineral volcanic
stratigraphy as follows (from bottom to top; Figure 7-2):
•
A massive to very crudely stratified, volcanic breccio-conglomerate unit with
angular to rounded boulder and lapilli-sized lithic clasts, in a feldspar-biotitehornblende-(quartz) crystal-rich volcaniclastic matrix (Tdbct); this unit grades
upward into a better-stratified, typically less coarse-grained sequence of similar
(probably dacitic) composition (Tdlbtgc).
•
Overlying these units, a texturally distinctive, pale-green coloured, largely matrixsupported crystal-lithic tuff (Tdlbxt), composed of a feldspar-hornblende, crystal-
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rich matrix with pale-green, boulder- to lapilli-sized sub-rounded feldsparhornblende porphyry clasts. This unit grades laterally into a poorly exposed, but
extensive volcanic breccio-conglomerate unit with small boulder- to lapilli-sized
polylithic (but predominantly porphyritic) clasts, supported within a sandy (to locally
more ashy) crystal-rich, volcaniclastic matrix (Tdlbt).
•
Forming much of the upper part of the volcaniclastic pile, there is a series of pebbly
to lapilli-sized lithic tuffs with an ashy to fine-broken crystal-rich matrix, with inferred
dacitic composition (CMflt, Tdflt, Tdflt2).
Figure 7-2:
Simplified Geologic Map of the Pantanillo Prospect (Source: Kinross,
quoted by Siddeley, 2009)
N
The lower part of the exposed volcaniclastic stratigraphy is correlated with the
Astaburuaga formation of Oligocene age (30 Ma to 35 Ma), while the upper part of the
volcanic section is assigned to an overlying late Oligocene to early Miocene age (2621 Ma) sequence largely comprised of tuffs and pyroclastic breccia units.
The volcanic sequence was intruded by a flow-dome complex composed of a series of
compositionally closely-related, feldspar-hornblende-(biotite-quartz) porphyritic units,
interpreted as a high-level felsic flow-dome complex (Figure 7-2; Figure 7-3). This
complex exhibits a NW-SE-elongated, slightly ovoid shape, probably reflecting the
controlling structures, and covering approximately 2.5 km2.
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Some of the flow-dome complex units show well-developed flow-banding or platy
foliation, generally concordant or sub-concordant with the generally shallow N to NEdipping host volcaniclastic stratigraphy. A monomictic, porphyry-breccia unit,
interpreted by Callan (2006) as an auto-breccia or carapace-type breccia, occupies the
highest levels within the dome complex.
Figure 7-3:
Geologic Map of the Pantanillo Norte Property (Source: Orosur)
A petrographic study conducted by Petrascience Inc. (Petrascience), quoted by Callan
(2006), described the porphyritic units as feldspar-hornblendic, locally biotite-phyric,
with very rare quartz phenocrysts. Little or no quartz was noted in the groundmass.
The petrographic study noticed the remarkable compositional similarity between
samples from texturally distinct outcrops, ranging from sub-concordant, strongly flowbanded porphyritic units to more massive, granular, porphyry lithologies.
Consequently, the study concluded that these lithologies would possibly correspond to
a single unit or series of compositionally very closely related units. Potassic feldspar is
present at deeper drill levels, but Siddeley (2009) suggests that it may be of primary
origin, not linked to later alteration.
Although Petrascience classified most of the studied samples as porphyritic andesite
or andesite porphyry, Callan (2006) indicated that previous whole-rock geochemical
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studies suggested a more felsic composition, which would be more consistent with the
strongly flow-banded nature of several porphyritic units within the flow-dome complex.
The flow-dome units cross through most of the preserved pre-mineral stratigraphy, but
unlike the host volcanic sequence, they have not been widely affected by pervasive
hydrothermal alteration. Instead, the flow-dome units are mainly altered in the
proximity of mineralized structures. Callan (2006) considered this as an indication of a
somewhat late timing for emplacement of the flow-dome complex, although admitted
that the compact, impermeable nature of the porphyritic units may also have limited
the pervasive alteration in these units.
A series of WNW-ESE (locally NW-SE)-striking, sub-vertical breccia units (Tpmbx)
have been mapped in the area. These units exhibit tabular to locally irregular
geometry, and reach up to 50 m width. The breccia units are largely clast-supported
and chaotic, and show pervasive advanced-argillic alteration. Callan (2006) considered
that these breccias had phreato-magmatic origin. The breccias postdate the formation
of the Au-porphyry mineralization, as suggested by the presence of porphyry veinletmineralized clasts.
Quartz-alunite ledges are commonly found in the Property, closely resembling the
A post-mineral ignimbritic sequence, lacking hydrothermal alteration (Sierra de la Sal
beds), covers discordantly and with sub-horizontal dips the mineralized and
hydrothermally altered volcanic and flow-dome units. This ignimbritic sequence is
dominated by massive to crudely stratified, compact feldspar-biotite-hornblende-quartz
crystal-bearing vitric units (Tig). Other lithologies present in the sequence are poorlysorted ignimbritic-lithic clast tuff breccias (Tigtbx), locally occuring at the base of the
ignimbritic section, a red-weathering, quartz-poor fine-lithic lapilli tuff (Tiglt), and
crystal-rich tuffs with sparse matrix-supported ignimbritic intra-clasts (Tigt) forming
cliffs on the eastern edge of the property.
7.3.2
Alteration
Raab (2010) has identified the following alteration assemblages at the Property:
•
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Structurally controlled, quartz-alunite-pyrite-hematite ledges with associated
advanced argillic ± silicified selvages
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•
Widespread kaolinite-goethite-hematite (after pyrite)-bearing argillic assemblages
associated with the uppermost andesite porphyry volcanics.
•
Widespread chlorite ± magnetite ± pyrite ± silica assemblage, associated with the
porphyry andesite and breccia intrusions.
•
Advanced argillic alteration selvages at the late phreato-magmatic breccias.
The close spatial relationship between the main alteration assemblages at Pantanillo
Norte is attributed to common structural pathways used by sub-volcanic intrusive host
rock units, porphyry-style vein swarms, ledge structures, and their respective
magmatic fluids sourced from a deep-seated magmatic system.
7.3.3
Structure
Callan (2006) identified and described the controlling role of various structures in the
geological evolution of the Property, in particular on the deposition and preservation of
pre- and post-mineral volcanic facies, emplacement of the intrusive flow-dome
complex, distribution of Au porphyry-style vein mineralization, and the distribution of
lithocap-related alteration (Figure 7-4).
Bedding and Flow-Banding
Bedding in stratified volcaniclastic sequences and flow-banding in the upper portions
of the flow-dome complex generally shows shallow N to NE dips, though localized dip
reversals and steeper dips are noted. Unconformably overlying units of the postmineral ignimbrite sequence similarly exhibit shallow N dips.
Faults
Various faults have been mainly identified due to related brecciation, or inferred from
local offsets or observed mis-match of volcanic units, mineralized structures or
alteration (Figure 7-4).
Regional Structures
The presence of a broad WNW-ESE-trending structural corridor crossing the area was
proposed by Callan (2006). This corridor (Figure 7-4) is largely defined by closely
juxtaposed, similarly striking, generally steeply dipping faults and fault-controlled silicic
or silica-alunite mineralized structures, the latter locally forming sub-parallel swarms.
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Figure 7-4:
Principal Structural Features of the Pantanillo Property (After Callan, 2006)
N
Legend: inferred structural corridors (blue hatch); faults and lineaments (blue lines); linear features from
magnetics (black); ledge structures (magenta, orange and red); Pantanillo N intrusive flow-dome (yellow).
The corridor is intersected in the Pantanillo N area by a NW-SE-striking, steeply
dipping structural trend. The NW-SE structures appear to control the porphyry
dyke/plug emplacement, silica ledge formation and phreato-magmatic brecciation.
The Property is located on the SE projection of a 30 km long, regional-scale NW-SEstriking structural zone linking the La Pepa high-sulphidation ledges and underlying Au
porphyry system, and the high-level breccia-hosted and porphyry-type Au
mineralization at Volcán Copiapó.
Structural Control
According to Raab (2010), the Au mineralization is controlled by the above-mentioned
structures, as well as by NNW-SSE and ENE-WSW trending structures. Porphyry vein
swarms have a predominant NW-SE strike, with moderate to steep dips between 50°75º to SW. A secondary subordinate control is NE-striking, with moderate dips (45°60º) to SE.
The structural control is also pronounced within robust quartz-alunite-pyrite
mineralized ledges, as which evidenced by the as following features:
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•
WNW-ESE to E-W-striking with steeper south-southwest dips at Veta Rosamaria, and
Veta Rosamaria Junior
•
ENE-WSW-striking with moderately steep SE dips at Veta Punto 14
•
Frequent NNW-SSE to N-S-striking, with sub-vertical to NE-dipping to the north of
Pantanillo Norte and in Pantanillo Central.
•
Minor variation or sinuosity along strike on individual structures is commonly exhibited,
and ledges often form broad, open and locally discontinuous structural meshes with
thickened bodies present at intersections.
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8.0
DEPOSIT TYPES
The Maricunga belt is characterized by the presence of numerous gold-rich, goldcopper porphyry deposits and prospects, as well as high-sulphidation epithermal
gold±copper±silver systems (Figure 8-1). However, the frequent superimposition of
both system types is characteristic for Maricunga, as opposite from the copperdominant, large porphyry copper systems found Northern and Central in Chile.
Figure 8-1:
Generalized Model of the Maricunga Porphyry-Epithermal Environment
(After Vila and Silitoe, 1991).
A synthesized description of the Maricunga belt mineralization was presented by Vila
and Sillitoe (1991):
Porphyry-type mineralization in the Maricunga belt was generated beneath
andesitic-(dacitic) stratovolcanoes. Volcanic rocks were intruded by isolated,
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composite dioritic porphyry stocks.
Weakly porphyritic microdiorite and
associated intrusion breccia are prominent stock components.
Gold-copper mineralization is believed to have been introduced with K-silicate
alteration, which is well preserved only at the Amalia, Refugio, and Casale Hill
(Aldebaran) prospects.
K-silicate alteration is overprinted and commonly
obliterated by sericite-clay-chlorite assemblages of intermediate argillic type.
Much of the gold is present in quartz stockworks. Iron oxides, both early
magnetite and late hematite, constitute 5 to 10 vol percent of mineralized zones.
Sulphides are dominated completely by pyrite but include minor chalcopyrite and
trace bornite and molybdenite. Supergene leaching of copper is developed to
various degrees, but enrichment is developed only incipiently.
Several porphyry-type stockworks are overlain by pyrite- and alunite-rich
advanced argillic alteration, which carries barite, native sulfur, enargite, and at La
Pepa, high-grade, vein-type gold mineralization of high sulphidation, epithermal
type. The quartz stockworks and advanced Argillic caps are telescoped at Marte,
Valy, Santa Cecilia, and La Pepa but are separated by a chloritized zone
transacted by a swarm of gold-poor, polymetallic veins with quartz-alunite
selvages at Aldebaran (Cerro Casale).
Marte and Lobo are rich in gold (1.43 and 1.6 ppm) and poor in copper (0.05 and
0.12%) and molybdenum (46 and ~10 ppm), and may be designated as porphyry
gold deposits. However, gold contents are lower (0.6-1 ppm) and hypogene
copper contents probably higher at Refugio and Casale Hill.
The depth of erosion of Maricunga porphyry-type systems is believed to
decrease from the K silicate zones exposed at Refugio and in the Casale Hill
sector at Aldebaran (Cerro Casale), through Marte, Valy, Santa Cecilia, and La
Pepa where remnants of advanced Argillic caps are present, to the highest,
mercury-rich part of the Cathedral Peak sector at Aldebaran and zones higher
than and west of Marte which comprise advanced argillic alteration rich in native
sulfur.
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9.0
MINERALIZATION
The Pantanillo mineralization features have been recently described by Siddeley
(2009) and Raab (2010). Sheeted-vein and stockwork-hosted gold occurs within the
hydrothermally-altered andesite porphyry in a sub-surface volcanic center.
Sheeted-vein sets and weak stockwork networks of quartz veinlets show textures
similar to those types documented in other Au-rich porphyry systems in the Maricunga
Belt (eg. Maricunga, Cerro Casale, and Marte). Au grade in core intersections with
strong banded-veining intensity commonly range from 1.0 g/t to 4.0 g/t, the higher
values being related to stronger vein swarm development.
Mineralized veinlets are hosted within the granular to porphyritic andesite volcanics
and the intrusion breccia units at Pantanillo Norte. Porphyry vein styles include:
•
Finely-banded veinlets, with grey-black quartz and magnetite
•
Translucent to dark grey, single-stage veinlets
•
White quartz veinlets.
Quartz-alunite ledges are spatially and temporally related to major structures on the
property, and develop at higher levels, forming roof structures to lower porphyry style
mineralization. The ledge features are generally considered to develop on deeptapping fault structures facilitating rapid ascent of magmatic volatiles.
Ledges are commonly tens to several hundred meters long, and decimetre up to 20 m
in width. However, these structures are discontinuous and volumetrically restricted,
and ledge-hosted Au mineralization at the Property is highly erratic, although it may
locally reach up to 2.5 g/t Au. Some ledges have undergone partial to locally extensive
re-brecciation.
According to Raab (2010), the ledge-hosted, high-sulphidation-style mineralization
postdates the porphyry-style Au mineralization, coincident with Muntean and Einaudi
(2001), who postulate that barren quartz-alunite at Aldebarán originated during early
porphyry mineralization, whereas gold-bearing ledges at La Pepa formed much later in
the evolution of the system (Figure 9-1).
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Figure 9-1:
Time-space Diagram for Typical Magmatic-hydrothermal Systems in the
Maricunga Belt (After Muntean and Einaudi, 2001).
described at the Property: oxide, mixed, and sulphide. The limits between these zones
have been conventionally defined on the basis of the following criteria:
•
Oxidation state of disseminated sulphides in the host rock
•
Oxidation state of the porphyry style quartz/magnetite/sulphide veins
•
Overall alteration of host rocks.
The oxide mineralization is mainly located in intensely weathered porphyry andesite
and locally andesite breccia. The lower limit has variable depth, but generally within
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the upper 170 m to 190 m on the eastern side of the Property, and within the upper 40
m to 60 m on the western side of the Property. Disseminated pyrite and magnetite
mineralization in the host rock, as well as quartz-magnetite-pyrite porphyry veining,
have been completely oxidized to hematite and limonite.
The mixed zone is hosted by both porphyry andesite and andesite breccia, with zones
of weak to moderate chlorite ± magnetite ± pyrite ± silica alteration inter-fingered with
moderate to weak argillic alteration. Depths are variable, but generally the mixed zone
is located between 190 m and 310 m depth on the eastern side of the Property, and
between 60 m and 280 m on the western side of the Property. Up to 5% disseminated
magnetite and pyrite mineralization may be common, showing only local patchy
oxidation. The quartz-magnetite-pyrite porphyry veining is oxidized to hematite and
limonite; however, it can be locally found unoxidized.
The sulphide zone is mainly hosted by breccia intrusion host rocks, with moderate to
strong chlorite ± magnetite ± pyrite ± silica alteration. The proportion of disseminated
magnetite and pyrite typically increases locally up to 10%. Depths are variable, but
generally the sulphide zone is below the 310 m depth on the eastern side of the
Property, and below the 280 m on the western side of the Property. Disseminated
magnetite and pyrite mineralization, and quartz/magnetite/pyrite porphyry veining, are
unoxidized.
A 0.3 g/t Au grade-shell representation of the mineralization at the Property shows two
main, very irregular bodies, and a series of smaller bodies, which taken as a whole
develop into a broad mineralized zone over 850 m long (NW-SE) and 300 m width,
dipping 30° to 45° SW. The identified mineralization reaches 600 m depth, but it
remains unconstrained downward.
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10.0
EXPLORATION
The main sources for the Pantanillo exploration history have been the reports prepared
by Callan (2005, 2006), and Siddeley (2009). This section contains excerpts from
those reports. However, they mainly refer to the exploration conducted starting from
the acquisition from Anaconda in 1983.
10.1
Anaconda Pre-1983 Exploration
In the early 1980’s, Anaconda conducted initial exploration activities on the Property;
however, no details have been available to AMEC about these activities.
10.2
AA 1983 to 1998 Exploration
The names of AA, EMMB and Anglo American Chile are used interchangeably in
documentation when referring to the companies that undertook exploration on the
Property between 1983 and 1998. AMEC will refer to these companies as AA in this
sectionto ensure simplicity and consistency.
Callan (2005) mentions that between 1983 and 1998 AA conducted broad exploration
activities in the area, including geological mapping, soil geochemistry, trenching,
trench/outcrop rock-chip sampling and drilling (RC and DD).
Various complex-anomaly geochemical maps (Au-Ag-Mo-Zn and Pb-As-Pb-Sb), and
1:5,000 and 1:2,000 scale geological maps (from 1985 and 1986, respectively) for the
Pantanillo Norte, Central and South and Quebrada Pantanillo are included in the digital
database supplied to AMEC. On one of the maps, the Pantanillo Norte target is well
marked by consistent Au (>0.08 ppm), Ag (>0.5 ppm), Mo (>10 ppm) and Zn (>200
ppm) anomalies. No details have been available about the exploration methods or
procedures followed for activities carried out during this period.
From 1988 to 1998, AA drilled 22 RC and 5 DD holes totalling 5,963 m. Details of the
drilling programs are discussed in Section 11.2.
10.3
Kinross 2005-2008 Exploration
Between 2005 and 2008, Kinross completed an extensive exploration program in the
Pantanillo area, which was described in detail by Callan (2006). Geological mapping at
a 1:5,000 scale over a 40 km2 area used a 60 cm resolution Quickbird™ topographic
surface for accurate spatial location. Detailed outcrop mapping facilitated by high-
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resolution base images was then conducted by a single Kinross geologist to ensure
consistency.
Alteration types were largely determined by hand-lens identification in the field, though
numerous samples were also collected for PIMA analysis to assist alteration
classification. A suite of 16 samples were submitted to Petrascience Inc. in Canada for
petrographic study and orientation PIMA work, with the aim of clarifying the intrusive
versus extrusive nature of porphyritic lithologies.
As a result of the mapping and alteration studies carried out by Kinross, geological
maps representing outcropping lithologies and interpreted geology and structure, as
well as a corresponding alteration and mineralization map showing principal altered
outcrops, mineralized structures and mineral occurrences, were prepared. After the
conclusion of this work in 2006, no new geological mapping has been carried out.
Argeli Geofisic EIRL conducted 954 line-km of ground magnetic survey at 50 m/100 m
line spacing. This survey emphasized the structural framework, and showed a large
negative anomaly over hydrothermally-altered areas, and positive anomalies over the
breccias and the andesitic intrusive at Pantanillo Norte.
Available Kinross reports (Callan, 2005, 2006) do not describe the geochemical
surveys conducted during this period, but Siddeley (2009) mentioned that 1,324 soil
samples and 210 rock samples were assayed to study the epithermal suite of
elements. Gold values tended to be generally low on surface, and the quartz ledges
showed a pathfinder assemblage of As/Sb/Hg/Ba. Quoting a report from Kinross dated
October 2006, Siddeley (2009) referred to a Au/Cu/Mo/Zn anomaly centred on
Pantanillo Norte, with 43 ppb to 618 ppb Au, 41 ppm to 537 ppm Cu, 5 ppm to 62
ppm Mo and 169 ppm to 510 ppm Zn, as well as Pb/As high anomalies in
Quebrada Pantanillo.
Callan (2006) concluded that Pantanillo Norte represents the only zone of significant
Au porphyry-style veining identified in the Property, and also indicated that a distinct
Mo signature commonly associated to the presence of Au porphyry mineralization was
only present at Pantanillo Norte. However, he pointed out that “… Drilling has
confirmed local economic intercepts defined in EMMB drilling and suggests veining
continues at depth though in many cases rather weakly developed and with likely
sub-economic Au tenor at deepest tested levels. My overall impression based on
drilling results to date is that zones of potentially economic stockwork Au
mineralization show poor continuity and are volumetrically restricted. Furthermore,
drilling by Kinross has not really significantly expanded the footprint of porphyrystyle Au mineralization beyond that defined by EMMB”.
Project No. 3107
October, 2010
Page 10-2
Orosur Mining Inc.
During this period Kinross drilled twelve DD and eight RC holes, as well as and one
combined DD/RC hole, totalling 8,929 m. Details of the drilling programs are discussed
on Section 11.3.
10.4
Orosur 2010 Exploration
Following the agreements between UME and FV signed in November 2009 (Section
4.3), Orosur started an infill drilling and re-sampling program on the Property.
10.4.1
Surveying
Drill-hole collars were initially marked by Orosur geologists using hand-held GPS
equipment. A topographic surveyor from Copiapó periodically are-surveyed the drillhole collars using differential GPS equipment. Control points with official Instituto
Geográfico Militar (IGM) coordinates were used for reference in the differential survey
work. At the time of AMEC´s site visit, Orosur was using the PSAD-56 datum in the
coordinate determinations. However, AMEC recommended Orosur to adopt the WGS84 datum, taking into consideration that this is the official datum in Chile. All the project
coordinates were subsequently transformed into the WGS-84 system.
Down-hole deviation measurements were completed by Orosur personnel at the
completion of each drill hole, using Reflex down-hole dip and magnetic azimuth survey
equipment. Readings were taken every 30 m ascending in most holes. No correction
for magnetic declination was used.
10.4.2
Drilling
OROSUR drilled 11 RC holes, totalling 1,854 m, and 19 DD holes, totalling 3,785 m.
Details of the Orosur drilling campaign are provided on Section 11.0.
10.4.3
Re-sampling
Orosur located the core from the 1988 AA campaign, and pulps from the 1997-1998
RC campaign. AMEC designed a re-sampling program in order to validate the old
assay database. Details of this re-sampling program and its results are provided in
Section 14.6.
Project No. 3107
October, 2010
Page 10-3
Orosur Mining Inc.
11.0
DRILLING
In total, approximately 20,531 m in 78 holes have been drilled on the Property since
1988. Of these, 36 holes (10,528 m) were DD, 41 holes (9,303 m) were RC, and one
hole (700 m) was pre-collared using RC drilling, and then drilled to final depth with
diamond drilling. Details of the various drilling programs are summarized in Table 11-1.
Figure 11-1 represents the drill-hole plan showing the different campaigns.
Table 11-1:
Company
Drilling Summary
Period
Anglo
American
1988
EMMB
Drill Hole
Prefix
Total
Holes
Length
Min
Max
(m)
(m)
Average
(m)
Drilling
Type
DDHPN01-03, 05,06
5
1,138
157
247
228
DDH
1997-1998
SR97PN-01 to 22
22
4,825
138
250
219
RC
Kinross
2006-2008
DDHPN-10, 16, PN-01
al 10
12
5,605
297
540
467
DD
Kinross
2006
ARPN-01, 03-09
8
2,624
192
414
328
RC
Kinross
2006
ARDDH-PN-02
1
700
700
RC/DD
19
3,785
120
267
199
DD
11
1,854
30.5
250
169
RC
78
20,531
Orosur
2010
Orosur
2010
PNN-10-01-06, 08-10,
12-13,15, 21-22, 2630DDH
PNN-10-07, 11, 14, 1620, 23-25RC
Total
11.1
Total
(m)
268
Anaconda Pre-1983 Drilling
There are references in the files provided by Orosur for 18 holes drilled by Anaconda
in the 70’s and/or early 80´s, but due to the lack of reliable information these holes
were not included in Table 11-1 nor in the Orosur database.
11.2
AA 1988 to 1998
Between 1988 and 1998, AA drilled twenty two RC holes, totalling 4,825 m, and five
DD holes totalling 1,138 m (Table 11-1). Most holes were inclined, with azimuth
between 3° and 20°, and with 60° inclination on average (Figure 4-1). No AA holes
exceeded 250 m depth. Other details about the AA drilling methods were not available
to AMEC.
Geological logging used alphanumeric codes for lithology, main ore and alteration
minerals indicating the intensity of alteration, gangue minerals, and details about
structure and quartz veinlets, and additional textual comments. Logging was recorded
in detailed standard-format sheets.
Project No. 3107
October, 2010
Page 11-1
Orosur Mining Inc.
Figure 11-1: Drilling Plan by Campaigns
Note: Red, AA; blue, Kinross; black, Orosur.
Siddeley (2009) indicates that AA geologists logged the geology encountered in the
drill holes as andesite porphyry or andesite breccia, and described mineralogical
zoning resulting from weathering as follows:
- A shallow (typically 70 m to 100 m depth) zone of oxidation, characterized by strong
to intense argillic alteration, abundant jarosite and hematite, patchy silicification (either
banded or pervasive), small amounts of gypsum disseminated or in veinlets, and
traces of barite
- A sulphide zone (beyond 100 m to the bottoms of holes, around 250 m depth) with
propylitic alteration (chlorite, illite, magnetite) with patches of disseminated pyrite
(typically 3%, reaching 7% in places). Argillic, silicic alteration and iron oxides
decrease significantly. It was noted that higher gold values, in the range of 0.3 g/t to
0.5 g/t in the sulphide zone, do not generally coincide with the logged appearance of
Project No. 3107
October, 2010
Page 11-2
Orosur Mining Inc.
pyrite. Potassic alteration was noted at deeper levels of DDHPN05 in the sulphide
zone.
A transitional, mixed zone was also apparent at 70 m to 100 m depth, where
argillic/hematite alteration patches typical of the oxide zone are interspersed with the
chlorite/pyritic propylitic variety.
11.3
Kinross 2006 to 2008
Between 2006 and 2008, Kinross drilled 12 DD holes, totalling 5,605 m, eight RC
holes, totalling 2,624 m, and one pre-collared RC/DDH hole of 700 m length. Diamond
drilling was conducted with UDR-1000 rigs, and drilling diameter was mainly HQ (63.5
mm). Core recovery was usually good (over 90%); only two holes had lower
recoveries, but recovery always exceeded 84%. RC drilling diameter was mainly 5¾",
and dry RC samples weighed 60 kg to 70 kg on average. RC recovery was not
calculated. No other details about drilling methods used by Kinross were available to
AMEC. The resulting drilling grid was approximately 100 m x 100 m. Collar locations
are shown in Figure 11-1.
Figure 11-2: Scissor-type drilling by Kinross (After Siddeley, 2009)
Project No. 3107
October, 2010
Page 11-3
Orosur Mining Inc.
Down-hole surveys were conducted by Comprobe, using a gyroscope/accelerometer,
with measurements every 10 m downward and every 50 m upward. Most Kinross
holes followed the orientation used by AA, but some holes were oriented to the south,
to scissor other holes (Figure 11-2). One hole reached 700 m depth, but the rest
ranged from 192 m to 540 m depth (Table 11-1).
Core boxes were photographed in three-box sets. Geological logging followed the 2 m
sampling pattern, and used numeric codes for lithology, alteration, mineralization type,
structure details and banded quartz veining (Table 11-2) on detailed standard-format
sheets. Summary logs with lithology, alteration, mineralization and veinlet type were
also prepared for each hole. In addition, geotechnical logging recorded the RQD,
structure type, condition and position, fracture filling and surface roughness, and rock
estimated resistance (IRS).
Table 11-2:
11.4
Logging Codes Used by Kinross in Core and RC Logging
Parameter
Code
Parameter
Code
Parameter
Lithology
Code
Alteration
Code
Mineralization Type
Gravels
Dacitic-andesitic dome
Intrusive breccia
Diorite
Granodiorite
Dacitic tuff (post-mineral)
Monzonitic porphyry
Ledge
Litic tuff
0
1
2
3
4
5
6
7
8
Structure
Fault
Fracturing
Fault breccia
Quartz ledge
1
2
3
4
Fresh
Supergene argillic
Hypogene argillic
Propylitic (chloritic)
Silicification
Quartz-alunite
Vuggy silica
Alunite
0
1
2
3
4
5
6
7
Code
Oxide
Sulphide
Mixed
1
2
3
Banded Quartz Veining
Scarce (< 3 per metre)
Moderate (3 to 5 per metre)
High (>5 per metre)
1
2
3
Orosur 2010
Orosur started a drilling campaign at the Property in early February 2010. Boart
Longyear and Perfoandes were the drilling contractors for DD and RC drilling,
respectively. In total, Orosur drilled 19 DD holes (3,785 m) and 11 RC holes (1,854 m).
Twenty eight holes were inclined, with 011° azimuth and -60º NNE inclination; one
hole was inclined at 80°, and another hole was vertical. Drilling was planned on
sections located between the previous 100 m-spaced drilling, in order to complete a 50
m section-spacing coverage. The resulting drilling grid was approximately 100 m x 50
Project No. 3107
October, 2010
Page 11-4
Orosur Mining Inc.
m. Drilling statistics are presented in Table 11-1. Collar locations are shown in Figure
11-1.
11.4.1
Core Drilling and Logging
AMEC visited the Property at the start of the drilling campaign, and reviewed the core
drilling and logging methods used by Orosur. Boart Longyear used an LF-90-D
Longyear rig for core drilling. Core diameter was HQ3 (61.1 mm), on 3 m long runs.
Core was hydraulically extracted from the core barrel, and placed on a 4 m long steel
channel. Orosur had a drilling supervisor permanently on every drill site. The controller
calculated the length recovery of each drilled interval, and measured RQD and density
of fractures as part of a full geotechnical logging procedure.
The Orosur drill supervisor transferred the core into 1 m long wood boxes, and put
marks every 2 m on the box sides as references for sampling. The core boxes were
identified with permanent marker indications (drill-hole name, box number, from and
to). Small wooden blocks were used to mark the ends of the drill runs. Core length
recovery was in general good, averaging 93%. Core boxes were transported by truck
to a secure storage facility at the Pantanillo camp twice a day at the end of each shift.
The core boxes were covered during transportation. All core boxes are currently stored
at the Orosur field office and core-logging facility in Copiapó.
After arrival to camp, core boxes were photographed in two-box sets, and then logged
and sampled. The geological logs record the main lithology and mineralization types in
coded, textual form. Details about the mineralization style such as main alteration
minerals and estimated percentages of CaCO3, Fe-oxide minerals, Cu-oxide and
sulphide minerals, and comments on texture, color, paragenesis, presence of veinlets
and structures. The alphanumeric codes used for logging at Pantanillo are shown in
Table 11-3. Logging was recorded in detailed standard-format sheets.
AMEC’s inspection of drill core during the site visits confirmed that the logging
protocols were correctly used. AMEC considers that the logging protocols and
information collected are appropriate for defining mineralization controls for resource
and reserve estimation.
11.4.2
RC Drilling and Sampling
RC drilling used a Drill Tech D40KX truck-mounted rig, and the RC diameter was 5 ½″.
At the time of AMEC’s site visit the RC rig was not active. However, AMEC was
advised that samples were weighed with a scale, and split with a Gilson splitter (14
shoots, 1.5 cm each. RC samples were systematically taken on 1 m intervals. The
Project No. 3107
October, 2010
Page 11-5
Orosur Mining Inc.
average sample weight was 40 kg. After successive splitting operations, the RC
samples were reduced to 5 kg for preparation and assaying. The rest of the material
was stored in plastic bags as backup. Representative samples from each interval were
collected in plastic chip trays for logging. Average RC weight recovery was 86%.
Logging was recorded in similar standard-format sheets and used the same lithology
codes as for DD. All RC samples are currently stored at the Orosur field office and
core-logging facility in Copiapó.
Table 11-3:
Logging Codes Used by Orosur in Core and RC Logging
Parameter
Lithology
Gravels
Dioritic Porphyry
Andesitic Porphyry
Dacitic-Andesitic Porphyry
Post-mineral Porphyry
Lithic Tuff
Volcanic breccia
Hydrothermal breccia
Intrusive breccia
Ledge breccia
Veinlets
Biotite veinlets
Biotite-magnetite veinltes
Magnetite veinlets
A-type veinlets (quartz±pyrite, chalcopyrite)
Transitional veinlets
Chlorite veinlets
Banded quartz-magnetite veinlets
D-type veinlets, with quartz-sericite halo
Pyrite venlets, with no alteration halo
Quartz-alunite ledge
Mineral Zone
Bottom of limonite
Oxide zone
Oxide bottom
Mixed zone
Bottom of mixed zone
Sulphide zone
Project No. 3107
October, 2010
Code
OGV
IDO PO
VAN
PO
PDA
PPM
VTL
BXV
BXH
BXI
BXG
Bt
Bm
M
A
T
Cl
B
D
P
QLU
PL
OX
PO
MX
PM
SX
Page 11-6
Parameter
Code
Structures
Fault with salband (741)
Dykes (744)
Fractures (Z Frac) (741)
Fault breccia (741
Quartz veins and veinlets (737)
Milled zone (Z Mol) (741)
GFJ
DK
FR
BR
QVV
MZ
Alteration Association
Argillic alteration (734½)
Quartz-sericitic alteration (758)
Sericitic-quartz alteration (758)
Chloritic alteration (738½)
Propylitic alteration (739)
Potassic alteration (743)
Silicification (735)
Supergene alteration (737)
ARG
QSE
SEQ
CHL
PRP
POT
SIL
SUP
Alteration Type
Pervasive
Replacement
Cumulus
Selective
Veinlets
Fracture filling
Alteration Intensity
Traces
Weak
Moderate
Strong
Intense
P
R
CL
L
V
S
1
2
3
4
5
Orosur Mining Inc.
11.4.3
Significant Mineral Intersections
A list of significant intersections is presented in Table 11-4. Due to the bulk nature of
the mineralization, true thickness could not be calculated.
11.4.4
Exploration Potential
The deposit may have additional exploration potential for sulphide mineralization in the
deeper horizons, particularly toward southwest, and below the ignimbritic cover in the
south-east.
AMEC recommends drilling seven 500 m long drill holes in sections 3NW, 5NW, 6NW,
7NW, 10NW, 12NW and 16NW (totalling 3,500 m), in order to delimit the
mineralization at depth toward the southwest. In addition, three 500 m deep drill-holes
(totalling 1,500 m) are recommended in the south-eastern portion of the Property, to
determine the potential below the ignimbrite cover.
Table 11-4:
Hole-ID
DDHPN02
DDHPN02
DDHPN02
DDHPN03
DDHPN03
DDHPN06
DDHPN06
SR97PN01
SR97PN01
SR97PN01
SR97PN02
SR97PN03
SR97PN03
SR97PN04
SR97PN04
SR97PN04
SR97PN05
SR97PN05
SR97PN07
SR97PN07
SR97PN08
SR97PN09
SR97PN09
SR97PN12
SR97PN12
SR97PN13
SR97PN13
Project No. 3107
October, 2010
Significant Mineral Intersections in Selected Drill Holes
Campaign
From (m)
To (m)
Length (m)
Au (g/t)
AA 1988
AA 1988
AA 1988
AA 1988
AA 1988
AA 1988
AA 1988
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
42.4
92.0
144.0
54.0
200.0
14.5
78.0
244.0
82.0
4.0
148.0
18.0
50.0
190.0
2.0
44.0
82.0
6.0
124.0
178.0
40.0
2.0
36.0
30.0
60.0
130.0
156.0
47.9
116.0
243.0
62.0
246.0
52.0
156.7
250.0
110.0
72.0
164.0
38.0
70.0
236.0
18.0
174.0
174.0
72.0
146.0
238.0
56.0
16.0
74.0
48.0
221.0
148.0
174.0
5.5
24.0
99.0
8.0
46.0
37.5
78.7
6.0
28.0
68.0
16.0
20.0
20.0
46.0
16.0
130.0
92.0
66.0
22.0
60.0
16.0
14.0
38.0
18.0
161.0
18.0
18.0
1.237
0.485
0.788
0.645
0.581
0.724
0.723
1.150
0.440
0.636
0.714
0.675
0.865
0.399
1.413
0.789
0.600
1.214
0.585
0.490
0.491
0.581
0.404
0.628
1.229
0.492
0.602
Page 11-7
Orosur Mining Inc.
Hole-ID
SR97PN13
SR97PN13
SR97PN14
SR97PN16
SR97PN16
SR97PN17
SR97PN18
SR97PN18
SR97PN19
SR97PN20
SR97PN20
SR97PN21
SR97PN21
SR97PN21
SR97PN21
ARDDHPN-02
ARDDHPN-02
ARDDHPN-02
ARDDHPN-02
ARDDHPN-02
RPN-03
ARPN-04
ARPN-09
ARPN-09
DDH-PN-10
DDH-PN-10
DDH-PN-10
DDH-PN-10
DDH-PN-10
DDH-PN-16
DDH-PN-16
DDH-PN-16
PN-01
PN-01
PN-01
PN-01
PN-02
PN-02
PN-02
PN-02
PN-03
PN-03
PN-03
PN-04
PN-04
PN-04
PN-04
PN-04
PN-05
Project No. 3107
October, 2010
Campaign
From (m)
To (m)
Length (m)
Au (g/t)
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
EMMB 1997-1998
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2006
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
52.0
86.0
76.0
56.0
110.0
80.0
146.0
60.0
140.0
144.0
56.0
142.0
14.0
172.0
62.0
150.0
260.0
320.0
472.0
524.0
340.0
36.0
28.0
272.0
294.0
42.0
316.0
66.0
168.0
280.0
64.0
126.0
66.0
96.0
156.0
292.0
394.0
422.0
266.0
128.0
262.0
362.0
12.0
72.0
486.0
88.0
138.0
346.0
240.0
80.0
114.0
156.0
92.0
200.0
228.0
214.0
118.0
232.0
156.0
80.0
164.0
22.0
196.0
86.0
162.0
274.0
368.0
518.0
684.0
390.0
46.0
38.0
312.0
306.0
60.0
362.0
130.0
284.0
297.1
102.0
264.0
72.0
114.0
204.0
340.0
412.0
446.3
338.0
252.0
302.0
462.0
210.0
78.0
502.0
100.0
228.0
476.0
258.0
28.0
28.0
80.0
36.0
90.0
148.0
68.0
58.0
92.0
12.0
24.0
22.0
8.0
24.0
24.0
12.0
14.0
48.0
46.0
160.0
50.0
10.0
10.0
40.0
12.0
18.0
46.0
64.0
116.0
17.1
38.0
138.0
6.0
18.0
48.0
48.0
18.0
24.3
72.0
124.0
40.0
100.0
198.0
6.0
16.0
12.0
90.0
130.0
18.0
0.449
0.720
0.601
1.239
0.780
0.770
0.536
0.636
0.376
0.715
0.439
0.539
1.720
0.628
1.038
0.709
0.665
0.396
0.615
0.704
0.452
2.930
0.647
0.436
0.646
0.702
0.419
1.128
0.801
0.537
1.690
1.262
0.800
0.426
0.440
0.528
0.447
0.444
0.584
0.987
0.466
0.495
0.774
1.022
0.516
1.007
0.925
0.711
0.714
Page 11-8
Orosur Mining Inc.
Hole-ID
PN-05
PN-05
PN-06
PN-06
PN-06
PN-07
PN-07
PN-08
PN-08
PN-09
PN-09
PN-09
PN-09
PN-10
PN-10
PN-10
PN-10
PNN-10-01DDH
PNN-10-01DDH
PNN-10-02DDH
PNN-10-02DDH
PNN-10-03DDH
PNN-10-03DDH
PNN-10-04DDH
PNN-10-04DDH
PNN-10-05DDH
PNN-10-05DDH
PNN-10-06DDH
PNN-10-06DDH
PNN-10-06DDH
PNN-10-07RC
PNN-10-08DDH
PNN-10-09DDH
PNN-10-10DDH
PNN-10-11RC
PNN-10-12DDH
PNN-10-14RC
PNN-10-14RC
PNN-10-15DDH
PNN-10-15DDH
PNN-10-16RC
PNN-10-16RC
PNN-10-17RC
PNN-10-18RC
PNN-10-18RC
PNN-10-19RC
PNN-10-19RC
PNN-10-20RC
PNN-10-20RC
Project No. 3107
October, 2010
Campaign
From (m)
To (m)
Length (m)
Au (g/t)
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Kinross 2008
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
336.0
124.0
146.0
264.0
292.0
158.0
368.0
164.0
310.0
474.0
142.0
174.0
312.0
182.0
376.0
206.0
282.0
60.0
130.0
108.0
202.0
140.0
26.0
230.0
150.0
48.0
140.0
140.0
4.0
82.0
130.0
42.0
124.0
22.0
14.0
124.0
111.0
47.0
0.0
180.0
169.0
77.0
116.0
144.0
59.0
2.0
44.0
38.0
3.0
424.0
232.0
152.0
284.0
460.0
224.0
498.0
246.0
452.0
494.0
168.0
232.0
428.0
200.0
426.0
272.0
360.0
72.0
201.4
162.0
240.0
195.9
92.0
257.5
224.0
54.0
224.0
168.0
76.0
122.0
167.0
100.0
132.0
30.0
44.0
156.0
126.0
101.0
20.0
221.0
200.0
107.0
184.0
200.0
133.0
34.0
114.0
56.0
32.0
88.0
108.0
6.0
20.0
168.0
66.0
130.0
82.0
142.0
20.0
26.0
58.0
116.0
18.0
50.0
66.0
78.0
12.0
71.4
54.0
38.0
55.9
66.0
27.5
74.0
6.0
82.0
28.0
72.0
40.0
37.0
58.0
8.0
8.0
30.0
32.0
15.0
54.0
20.0
41.0
31.0
30.0
68.0
56.0
74.0
32.0
70.0
18.0
29.0
0.533
0.541
1.236
0.437
0.878
0.364
0.563
1.125
1.126
0.429
0.519
0.939
0.851
1.086
0.611
0.472
0.802
1.408
0.937
0.530
0.771
0.791
0.932
0.989
1.381
0.999
0.526
0.522
0.553
1.366
0.484
0.571
2.226
0.932
0.560
0.514
0.655
0.679
1.319
1.503
0.377
0.458
0.974
0.584
0.936
1.089
0.925
0.549
0.943
Page 11-9
Orosur Mining Inc.
Hole-ID
PNN-10-21DDH
PNN-10-22DDH
PNN-10-22DDH
PNN-10-23RC
PNN-10-24RC
PNN-10-27DDH
PNN-10-27DDH
PNN-10-27DDH
PNN-10-27DDH
PNN-10-29DDH
PNN-10-30DDH
Project No. 3107
October, 2010
Campaign
From (m)
To (m)
Length (m)
Au (g/t)
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
Orosur 2010
188.0
160.0
78.0
28.0
27.0
24.0
170.0
230.0
82.0
84.0
202.0
218.5
175.1
106.0
137.0
87.0
30.0
200.0
250.0
162.0
92.0
266.0
30.5
15.1
28.0
109.0
60.0
6.0
30.0
20.0
80.0
8.0
64.0
1.001
0.586
1.166
0.369
0.412
1.817
0.447
0.925
0.618
1.109
0.813
Page 11-10
Orosur Mining Inc.
12.0
SAMPLING METHOD AND APPROACH
12.1
AA 1988 to 1998
A systematic 2 m sampling interval was used during this period, both for RC and for
DD drilling. AMEC has no other documented references about the sampling methods
used during the AA drilling campaigns.
12.2
A systematic 2 m sampling interval was used during this period, both for RC and for
DD drilling. AMEC has no other documented references about the sampling methods
used during the Kinross drilling campaigns.
12.3
Orosur 2010
During the logging operation, a geologist marked the cutting line on the core, which
had to be followed by samplers. As a rule, core sampling was systematic and sample
length was 2 m, but major lithology and/or alteration contacts were taken into
consideration when delimiting the sample intervals. RC sampling was also systematic,
and sample length was 1 m.
Core was cut in half with a standard diamond-saw core cutting machine. Sample
weight was 5 kg to 6 kg on average. Samples were bagged and stored in large plastic
bags. Submission batches were usually arranged by drill holes with one hole per
batch. Trucks from ACME, the primary laboratory for the Orosur campaign, regularly
collected the samples from the camp.
Project No. 3107
October, 2010
Page 12-1
Orosur Mining Inc.
13.0
SAMPLE PREPARATION, ANALYSES, AND SECURITY
13.1
AA 1988 to 1998
AMEC has no documented references about the sample preparation and assaying
methods used during the AA drilling campaigns.
13.2
Kinross used ALS Chemex La Serena as primary laboratory.
Sample preparation was as follows:
•
Crushing to 90% minus 2 mm (10 mesh ASTM)
•
Splitting to obtain a 1,000 g sub-sample
•
Pulverization to 85% minus 0.075 mm (200 mesh Tyler).
Pulps were assayed for Au, Cu, sodium cyanide-soluble Cu (CuCN), and sodium
cyanide-soluble Au (AuCN). Details of the assay methods are presented in Table 13-1.
Table 13-1:
Elements and Grade Ranges of ALS Assay Methods
Element
Method
Details
Detection
Limit (ppm)
Au
Au-AA24
FA with AAS finish, 50 g aliquot
0.005
Upper
Limit
(ppm)
10
Cu
Cu-AA61
1
10,000
0.05
10
1
10,000
AuCN
AuCN-LS01
0.25 g aliquot, HF-HNO3-HClO4 acid
digestion, HCl leach, AAS reading
20 g aliquot, NaCN leach, AA reading
CuCN
CuCN-LS01
NaCN leach, AA reading
FA: Fire assay; AAS: Atomic absorption spectrometry
13.3
Orosur 2010
ACME Santiago was the primary laboratory for the assaying carried out during Orosur
2010 campaign. Samples were prepared at Copiapó, where ACME has a preparation
facility, and later transported to Santiago for assaying.
Sample preparation was as follows:
•
Project No. 3107
October, 2010
Drying at 60°C
Page 13-1
Orosur Mining Inc.
•
Crushing to 100% minus 12 mm
•
Splitting in two portions, and storing one split (50%) for metallurgical studies
•
Crushing the second split (50%) to 80% minus 2 mm (10 mesh ASTM)
•
Homogenization and splitting to obtain a 500 g sub-sample
•
Pulverization to 85% minus 0.075 mm (200 mesh Tyler).
Pulps were assayed at ACME for Au by the G6-50 method, consisting of Fire Assay
(FA) with Atomic Absorption Spectrometry (AAS) finish, using 50 g aliquots. The
detection limit was 5 ppb.
All pulps were also assayed by the ICP Group 1E method for 36 elements. This
method uses a 0.25 g aliquot, which is digested and heated in HNO3-HClO4-HF to
fuming, and then taken to dryness. The residue is dissolved in HCl. Solutions are
analysed by ICP-ES. The elements and corresponding grade ranges are listed in
Table 13-2. Assay results were reported via e-mail.
Table 13-2:
Elements and Grade Ranges of ACME Method Group 1E
Element
Unit
Detection
Limit
Upper
Limit
Element
Unit
Detection
Limit
Upper
Limit
Ag
Al
As
Au
Ba
Be
Bi
Ca
Cd
Co
Cr
Cu
Fe
K
La
Mg
Mn
Mo
ppm
%
ppm
ppm
ppm
ppm
ppm
%
ppm
ppm
ppm
ppm
%
%
ppm
%
ppm
ppm
0.5
0.01
5
4
1
1
5
0.01
0.4
2
2
2
0.01
0.01
2
0.01
5
2
200
20
10000
200
10000
1000
4000
40
4000
4000
10000
10000
60
10
2000
30
10000
4000
Na
Nb
Ni
P
Pb
S
Sb
Sc
Sn
Sr
Th
Ti
U
V
W
Y
Zn
Zr
%
ppm
ppm
%
ppm
%
ppm
ppm
ppm
ppm
ppm
%
ppm
ppm
ppm
ppm
ppm
ppm
0.01
2
2
0.002
5
0.1
5
1
2
2
2
0.01
20
2
4
2
2
2
10
2000
10000
5
10000
10
4000
200
2000
10000
4000
10
4000
10000
200
2000
10000
2000
Project No. 3107
October, 2010
Page 13-2
Orosur Mining Inc.
14.0
DATA VERIFICATION
14.1
Drill-Hole Collar Review
AMEC reviewed the coordinates of 15 drill holes from three drilling campaigns (AA
1987/88, Kinross 1998, y Orosur 2010; Table 14-1) with a Garmin e-Trex GPS, and
compared the results of these measurements with the coordinates determined by the
project surveyor. In spite of the fact that the conventional GPS measurements are less
precise than measurements conducted with more sophisticated equipments, this
procedure allows the identification of gross surveying errors.
Table 14-1:
Collar Coordinate Check (Corrected PSAD-56 Measurements)
AMEC
Hole ID
Easting
(m)
Orosur
Northing
(m)
Easting
(m)
Northing
(m)
Absolute
Difference
Easting Northing
(m)
(m)
Campaign
SR97PN04
493037
6965235
493,035
6,965,240
2.4
5.0
AA-1987/88
SR97PN06
493196
6964999
493,194
6,965,001
2.1
2.4
AA-1987/88
SR97PN07
492668
6965338
492,668
6,965,341
0.5
2.7
AA-1987/88
SR97PN09
493055
6965337
493,054
6,965,338
1.3
0.6
AA-1987/88
SR97PN12
492575
6965386
492,569
6,965,378
5.5
8.0
AA-1987/88
SR97PN22
493215
6965093
493,213
6,965,098
2.0
4.8
AA-1987/88
PNN-10-03
492983
6965221
492,984
6,965,219
0.9
2.3
Orosur-2010
PNN-10-05
492868
6965142
492,869
6,965,139
1.4
3.3
Orosur-2010
PNN-10-06
492904
6965337
492,905
6,965,335
0.7
2.1
Orosur-2010
PN-03
493055
6965337
493,056
6,965,338
1.2
0.7
Kinross-1998
PN-05
492822
6965143
492,819
6,965,147
3.1
4.4
Kinross-1998
PN-09
492622
6965604
492,631
6,965,608
9.1
3.7
Kinross-1998
PNN-10-07
493120
6964890
493,121
6,964,887
1.0
3.3
Orosur-2010
PNN-10-08
492821
6965353
492,823
6,965,348
1.8
5.4
Orosur-2010
2.3
3.5
Average Absolute Difference
At the time of the site visit, Orosur was still using the PSAD-56 datum16, which has a
systematic local difference of approximately -23 m in the easting and 40 m in the
northing as compared with the standard PSAD-56 datum coordinates. The maximum
absolute differences between Orosur PSAD-56 coordinates and AMEC’s corrected
readings were 2.3 m for easting and 3.5 m for northing. Two readings in the easting
and two readings in the northing exceeded 5 m absolute difference, but none of them
exceeded 10 m. AMEC is of the opinion that those differences were within the
acceptable error of a conventional GPS device.
16. After AMEC’s site visit, Orosur adopted the WGS-84 datum.
Project No. 3107
October, 2010
Page 14-1
Orosur Mining Inc.
14.2
Database Checks
14.2.1
Hard-Copy Drill-Hole Folders
Orosur keeps ordered hard-copy files for each drill hole at the Santiago office. AMEC
reviewed six drill-hole folders belonging to the Orosur 2010 campaign (PNN-10-01 to
03; PNN-10-13 to 15), corresponding to 20% of the 30 drill holes from the 2010
campaign. The reviewed folders were well organized, and included drilling reports,
recovery data, geological and geotechnical logs, and copies of original assay
certificates. However, none of them included collar original collar coordinate data, and
two of them did not include collar survey data. AMEC recommends that the drill-hole
folders be completed with original (or copies of) collar and down-hole survey
documents.
14.2.2
Collar and Down-Hole Surveys
AMEC reviewed the collar survey information included in six drill-hole folders
belonging to the Orosur 2010 campaign (PNN-10-01 to 03; PNN-10-13 to 15), and
compared the original data with the database entries. None of the drill-hole folders
included original collar survey data. Although digital files were available, only the
projected collar coordinates and orientation figures were found in the folders.
AMEC also reviewed the down-hole survey information included in the same folders,
and compared the original data with the database entries. Two folders (PNN-10-1 and
PNN-10-3) did not include the down-hole survey documents. No transcription errors
were identified in the other four folders.
14.2.3
Original Logs: Lithology, Alteration and Mineral Zone
Original logs from the AA and Kinross campaigns were not available for review.
AMEC reviewed the lithology, alteration and mineral zone codes on original logs from
six drill holes belonging to the Orosur 2010 campaign (PNN-10-01 to 03; PNN-10-13 to
15), and compared them with the corresponding records in the final database.
No errors were identified in the alteration field. However, AMEC noticed that a general
correspondence is observed in the lithology and mineral zone fields, but the database
only includes simplified codes from geological interpretation. AMEC recommends that
original lithology and mineral zoning coding be included as additional fields in the
database.
Project No. 3107
October, 2010
Page 14-2
Orosur Mining Inc.
14.2.4
Original Certificates
AMEC requested that ACME provide the original 2010 assay data, both in Excel and in
PDF format. AMEC used these data, directly provided by the laboratory, to compile an
independent assay database, and compared these values with the Orosur project
database. During this process, some transcription errors were identified, but all of them
were corrected. The final database is free from transcription errors.
14.3
Core Description and Geological Interpretation
During the site visit, AMEC reviewed the core from two drill holes (PNN-10-06 and
PNN-10-08) and the corresponding geological logs. AMEC observed that lithology,
alteration, structure and mineralization were properly described, and that major
contacts were correctly indicated.
AMEC reviewed the geometry of the interpreted geological and alteration shapes in 19
50 m-spaced, NE-SW-oriented cross-sections (1 to 19) on a computer screen. The
sections also included shapes for mineralized zones, corresponding to the
mineralization type (leached, oxide, mixed and sulphide).
During the review, AMEC found discrepancies, which were corrected in the process of
preparing the geological model; however, AMEC recognizes that the interpretation
generally respects the data recorded in the logs and the sections, as well as the
interpretation from adjoining sections, and is consistent with the known characteristics
of this deposit type.
14.4
Down-Hole Contamination Analysis
AMEC investigated the possibility of RC down-hole contamination at Pantanillo during
the 2010 drilling campaign. This study was concerned with two specific down-hole
contamination problems that can occur in RC drilling: decay and cyclicity.
Decay is the tendency of contamination down-hole of mineralized intersections.
Cyclicity is considered to be the tendency of metal to concentrate at the bottoms of
holes during pauses in drilling, which typically occurs when rods are changed, but can
happen at any time during the drilling process. Collapse of unstable zones intersected
in RC holes tends to occur when drilling is stopped. Typically, decay and cyclicity are
linked, and grades can be enhanced by both factors.
Project No. 3107
October, 2010
Page 14-3
Orosur Mining Inc.
An evaluation of decay and cyclicity of assays from RC drilling is usually required to
determine if down-hole contamination has occurred below high grade intersections,
contacts, or during rod changes.
14.4.1
Decay
The decay software program written by AMEC (DECAYF) assists in locating
asymmetrical grade profiles that are skewed downward. Downward-skewed grade
profiles may be indicative of down-hole contamination. The program selects samples
with grades above a threshold supplied by the user and then identifies the grades in
the following positions:
Uphole
j-5 =
j-4 =
j-3 =
j-2 =
j-1 =
j
=
j + 1=
j + 2=
j + 3=
j + 4=
j + 5=
B(5)
B(4)
B(3)
B(2)
B(1)
sample meeting the threshold
A (1)
A(2)
A(3)
A(4)
A(5)
Down-hole
The relative differences are computed and summed as follows:
ACRD = ∑[A(i) - B(i)]/{[A(i)+B(i)]/2}
where ACRD is the accumulated relative difference, or total relative difference. A high
value of ACRD means that the down-hole values have higher grades. The program
prints out grade profiles where ACRD exceeds an input value, or the number of
positive differences meets an input threshold.
When the number of positive differences is set to 0, the program looks at all samples
that exceed the threshold value and summarizes the shapes of the profiles around all
of those samples. That summary provides a good idea of the average grade profile
around samples exceeding the threshold value. If the average profile is significantly
biased (skewed) downward, down-hole contamination is indicated.
Project No. 3107
October, 2010
Page 14-4
Orosur Mining Inc.
Table 6-3 is a summary of the Au data for various grade thresholds processed with
DECAYF for the 2010 drilling campaign. The average grade of each of the positions is
presented in the table. Positions -5 to -1 are above and positions 1 to 5 below the
sample in question. The average grades above (AGa) and below (AGb) the sample will
be approximately equal if the grade distribution is symmetrical. The grade ratio (AGa /
AGb) will be less than 1 if the distribution is skewed downward, suggesting
contamination; the lower the ratio, the skewer the distribution.
The Au grade ratios are close to 1 even considering samples with up to 3,000 ppb Au
(Table 14-2). On the basis of this analysis, AMEC determined that significant Au
decay-related down-hole contamination did not occur during the 2010 exploration
campaign.
Table 14-2:
Summary of Au Decay data at Various Grade Thresholds
Grade Threshold - Au (ppb) - Pantanillo
Position
-5
-4
-3
-2
-1
0
1
2
3
4
5
Mean -5 to -1
Mean 1 to 5
Ratio
N°. of Intervals
14.4.2
300
608
628
632
644
678
731
676
643
613
607
613
600
826
911
890
924
974
1217
963
903
823
850
860
1,000
1000
1061
1096
1271
1346
1756
1261
1266
1090
1115
1016
1,500
1302
1345
1422
1526
1708
2515
1641
1577
1331
1321
1183
2,000
1348
1289
1426
1586
1842
3165
1635
1595
1275
1175
1112
2,000
1348
1289
1426
1586
1842
3165
1635
1595
1275
1175
1112
638
630
1.012
651
905
880
1.029
254
1155
1149
1.005
116
1461
1411
1.035
48
1498
1358
1.103
26
1498
1358
1.103
26
Cyclicity
The cyclicity program developed by AMEC (CYCLEG) is based on the fact that each
sample position in a rod has an equal probability of being the highest-grade sample on
that rod in a random system. Significant departure from that probability is cause for
concern. For example, if a hole is eight rods deep and has five contiguous high grade
samples in position 1, the existence of cyclicity is suspected, since it is extremely
unlikely that this situation could occur naturally in a mineral deposit.
Project No. 3107
October, 2010
Page 14-5
Orosur Mining Inc.
Sometimes the cyclicity pattern is not strictly followed. Collapse of a mineralized zone
and subsequent contamination can occur at any time during drilling of the hole, and so
the high-grade spikes do not necessarily fall on rod breaks. Another difficulty is that,
depending on the drill site situation, the exact location of rod breaks can vary by one
sample position for different holes. The slope of the ground, angle of the hole, etc., can
determine whether the rod break is at 0 or 1 depth units. It is also possible, though
uncommon, for drilling to pause between rod breaks for any number of reasons. In this
instance, a grade spike due to contamination can occur within a rod rather than at the
breaks. For these reasons, much of the final analysis of the data is dependent on
experience with RC drilling rather than any type of numerical analysis.
AMEC prepared CYCLEG plots for the 11 RC holes drilled during the 2010 drilling
campaign, assuming 6 m rod length and 1 m sample length, and concluded that
significant Au cyclicity-related down-hole contamination did not occur during the
Orosur exploration campaign.
14.5
Twin Holes
Orosur did not drill twin holes during the 2010 campaign. In total, 41 RC drill holes
totalling 9,733 m have been drilled at the property. AMEC strongly recommends that
future exploration includes drilling twin holes with DD on 5% of the RC holes, including
RC holes from previous campaigns.
14.6
QC Protocols and Data
14.6.1
Definitions
CIM Best Practices Guidelines (CIM, 2000, 2003, 2005) recommend that a data
verification program accompany any exploration campaign to confirm validity of data.
Furthermore, the guidelines require that a QC program be utilized to ensure that
analytical accuracy and precision are adequate to support resource estimation.
As a rule, two laboratories are used during a QC program: a primary laboratory, where
all the regular samples are assayed, and a secondary (or umpire) laboratory, usually a
highly-reputed laboratory, where a representative portion of the samples assayed at
the primary laboratory are re-assayed. The QC program includes the regular
submission of the regular samples to the primary laboratory, accompanied by a certain
proportion of blind control samples, and the regular submission to the secondary
laboratory of a portion of the regular samples previously assayed at the primary
laboratory, also accompanied by a certain proportion of blind control samples.
Project No. 3107
October, 2010
Page 14-6
Orosur Mining Inc.
The purpose of the blind insertion of control samples is to prevent the laboratory from
identifying the control samples, or at least the nature and equivalency of the control
samples. All accredited laboratories have internal QC procedures, and usually assay
certificates include the results of the internal QC. However, some laboratories
customarily will only reveal those checks which pass their internal controls, but not the
failures. For this reason, the internal laboratory QC should not replace the client’s own
QC program.
An exploration QC program should monitor various essential elements, in an effort to
control or minimize the total possible error in the sampling-preparation-assaying
sequence:
•
Sample collection and splitting (sampling variance, or sampling precision)
•
Sample preparation and sub-sampling (sub-sampling variance, or sub-sampling
precision; contamination during preparation)
•
Analysis (analytical accuracy, analytical precision and analytical contamination).
•
Quality control is achieved through the insertion of control samples in appropriate
proportions, usually not exceeding 20% in total. A comprehensive quality control
protocol should include the following control sample types:
•
Twin samples are samples obtained by repeating the sampling in the proximity of the
original location. In the case of core drilling, such samples are usually obtained by resplitting the half-core samples, representing therefore one quarter of the core. In the
case of blast holes, the TS can be obtained by collecting a second sample from the
same cone (by placing a tray on the opposite position, for example). These samples
should be assayed in the same batch and by the same laboratory as the original
samples, and are mainly used to assess the core (or channel, or blast-hole) sampling
variance.
•
Field duplicates are samples taken from the first split of the original bulk RC samples,
immediately after drilling and without any previous crushing. These samples should be
prepared and assayed in the same batch and by the same laboratory as the original
samples, and are mainly used to assess the RC sampling variance.
•
Coarse duplicates (also referred to as coarse rejects or preparation duplicates) are
splits of coarse rejects taken immediately after the first crushing and splitting step.
These samples should be pulverized and assayed in the same batch and by the same
laboratory as the original samples. The coarse duplicates provide information about the
sub-sampling variance introduced during the preparation process.
•
Coarse blanks are coarse samples of barren material, which provide information about
the possible contamination during preparation; the coarse blanks should be prepared
immediately after highly mineralized samples.
Project No. 3107
October, 2010
Page 14-7
Orosur Mining Inc.
14.6.2
•
Pulp duplicates are second splits, or resubmission of prepared samples that are
routinely analyzed by the primary laboratory. These samples should be assayed in the
same batch and by the same laboratory as the original samples, or be resubmitted as
closely in time as possible to the same laboratory, under a different sample number.
The pulp duplicates are indicators of the assay repeatability or precision.
•
Fine blanks are pulverized samples of barren material, which provide information about
the possible contamination during assaying; these samples should be assayed
immediately after highly mineralized samples.
•
Standard Reference Materials (SRMs, or standard samples) are samples with well
established grades, prepared under special conditions, usually by certified commercial
laboratories. These samples are used to estimate the assay accuracy, in conjunction
with the check samples.
•
Check samples are equivalents of the above defined pulp duplicate samples, resubmitted in this case to an external certified laboratory (secondary laboratory). These
samples are used to estimate the accuracy, in conjunction with the SRMs.
AMEC QC Evaluation Processing
Duplicate Samples
AMEC evaluates the duplicate samples according to the Hyperbolic Method (Simón,
2004). The failure rate for each duplicate type is calculated by evaluating each sample
pair against the hyperbolic equation y2=m2x2+b2 with specific parameters for each
duplicate type. Sample pairs exceeding the y value so calculated are considered
failures. An acceptable level of precision is achieved if the failure rate does not exceed
10% of all pairs. Max-Min plots can be constructed for the studied elements, to
visualize the results, by plotting the maximum and minimum values of the sample pairs
in the y and x axis, respectively. This way, all the points are plotted above the x=y line.
The failure line is plotted according to the hyperbolic equation, and sample pairs
plotting above this line are considered failures.
SRMs
For evaluating the SRMs, control charts are built for each SRM and documented
element. The values reported for the inserted SRMs are plotted in a time sequence. In
principle, SRM values lying outside the AV±2*SD boundaries (AV, SD: average value
and standard deviation, respectively, calculated from the actual assay values of the
inserted SRMs) are considered outliers and rejected. However, isolated values within
the AV±3*SD limits are also accepted.
The analytical bias is calculated as:
Project No. 3107
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Orosur Mining Inc.
Bias (%) = (AVeo / BV) – 1
where AVeo represents the average value recalculated after the exclusion of the
outliers, and BV is the SRM Best Value, calculated as a result of round-robin test. The
bias values are assessed according to the following ranges: good, between -5% and
+5%; questionable, depending on the particular element, from -5% to -10% or from +5
to +10%; unacceptable, below -10% or above 10%. However, if AVeo-BV≤CI (CI:
confidence interval with 95% confidence calculated as a result of the round robin test),
then the bias is not measurable, and is considered as negligible.
Blank Samples
Blank versus Preceding Sample plots are prepared, which allow the identification of
possible incidents of cross-contamination during preparation and assaying.
Contamination is suspected if the blank value exceeds three to five times the detection
limit for the studied element, and/or if a definite, positive rapport is observed between
the blank grade and the grade of the preceding sample.
If the values of the preceding samples are not known, then control charts are
prepared, where the blank values are plotted on a time sequence. A safe line is
represented at the assumed contamination level, and the contamination rate is
calculated as the percentage of blank values above the safe line.
Check Samples
For evaluating the CSs, Reduction-to-Major-Axis (RMA) plots are constructed for the
studied elements. The RMA method offers an unbiased fit for two sets of pair values
(original samples and CSs) that are considered independent from each other. In this
case, the coefficient of determination R2 between the two laboratories is determined,
and the bias of the primary laboratory for each element as compared to the secondary
laboratory is calculated as:
Bias (%) = 1- RMAS
where RMAS is the slope of the RMA regression line of the secondary laboratory
values versus the primary laboratory values for each element. A detailed description of
the RMA method is presented in Appendix B.
14.6.3
AA QC 1988 to 1998
AMEC has no documented references about any QC protocol implemented during the
AA drilling campaigns; however, Orosur located most of the old AA pulps (initially
Project No. 3107
October, 2010
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Orosur Mining Inc.
assayed at Geolab), which allowed AMEC to organize an independent resampling
program. In total, 100 check samples were randomly selected (five samples from each
hole) and were submitted to ACME. Samples were assayed using the same protocols
as for the 2010 Orosur campaign (Section 13.3).
There was a good fit between both datasets, as indicated by the high values of the
coefficient of determination R2. The RMA analysis also showed that, after the
exclusion of outliers, the Geolab Au bias relative to ACME was 7.2% (Table 14-3;
Figura 14-1). There were no outliers for Cu, and the resulting bias of Geolab related to
ACME was 5.1%.
Table 14-3:
AA Check Assay RMA Regression Statistics
Pantanillo Project - RMA Parameters – AA Check Samples-All Samples
Element
Au (g/t)
Cu (%)
2
R
N (total)
Pairs
m
Error (m)
b
Error (b)
Bias
0.979
0.981
100
100
100
100
0.878
0.949
0.013
0.013
0.028
-0.002
0.018
0.001
12.2%
5.1%
Pantanillo Project - RMA Parameters – AA Check Samples-No Outliers
Element
Au (g/t)
Cu (%)
2
R
Accepted
Outliers
m
Error (m)
b
Error (b)
Bias
0.984
0.981
86
100
14
0
0.928
0.949
0.012
0.013
0.013
-0.002
0.010
0.001
7.2%
5.1%
Figure 14-1: ACME versus Geolab RMA Plot
Project No. 3107
October, 2010
Page 14-10
Orosur Mining Inc.
The check sample batch included 15 samples from three SRMs prepared by CDN
Resource Laboratories (CDN), ten pulp duplicates and five pulp blanks. The ACME
bias values ranged from -1.9% to -7.8% for Au, and from 1.5% to 1.6% for Cu (Table
14-4). Only one duplicate presented a failure, and the pulp blanks did not reveal
significant contamination during assaying.
By comparing Geolab’s and AMEC’s performance on Au assays, AMEC concluded
that the Au overestimation at Geolab relative to ACME was reasonably compensated
by ACME’s Au underestimation, as determined by inserted SRMs. As a result of this
resampling test, AMEC is of the opinion that the AA assay data appear to be
sufficiently precise and accurate for mineral resource and reserve estimation
purposes.
Table 14-4:
SRM ID
CM-5
CGS-19
GS-3F
14.6.4
2010 Resampling Test of AA Pulps: Au SRM Summary
Count
5
5
5
Average
(g/t)
0.333
0.765
3.295
BV
(g/t)
0.294
0.740
3.100
Outliers
1
1
0
Bias
(%)
-7.8
-1.9
-5.9
Average
(g/t)
0.314
0.130
0.016
BV
(g/t)
0.319
0.132
---
Outliers
0
0
0
Bias
(%)
1.6
1.5
---
Kinross QC 2006 to 2008
During the 2006 drilling program, the QC program implemented by Kinross included
the analysis of pulp duplicates with a frequency of one duplicate in 20 samples (5%).
In 2007, blanks and three reference materials were also inserted at irregular
frequencies, but the detailed QC data were not available to AMEC.
According to Siddeley (2009). 16 drill samples from the Kinross 2006 program
were subjected to independent FA assays in ALS Chemex and Acme using 50 g
aliquots, and most of values gave only small differences. Only three out of twelve
assays had differences of 50%, but at the low ppb level.
During the 2008 drilling program, Kinross implemented a QC program consisting of the
insertion of four SRMs (5.2%), pulp blanks (4.5%) and pulp duplicates (4.1%). AMEC
processed the available QC data. The pulp duplicate error rate was 2.5%, reasonable
considering an acceptable duplicate error rate limit of 10%. Most SRM values were in
control (only one outlier for one of the SRMs) and the bias values ranged between 0.3% and 3.6% (Table 14-5)
Therefore, AMEC is of the opinion that the analytical accuracy and precision from this
campaign are within reasonable limits for data supporting mineral resource and
reserve estimation. None of the blanks exhibited significant contamination.
Project No. 3107
October, 2010
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Orosur Mining Inc.
Table 14-5:
Kinross 2008 Campaign Au SRM Summary
SRM ID
CGS-12
CGS-P5B
CGS-P7A
CM-2
Mean
(g/t)
BV
(g/t)
Count
Outliers
Bias
0.29
0.44
0.75
1.44
0.28
0.42
0.75
1.42
30
24
27
26
0
1
0
0
3.2%
3.6%
-0.3%
1.7%
During this campaign, Kinross used ALS Chemex La Serena as primary laboratory.
ALS inserted various samples from up to four different Rocklabs Au SRMs in each
batch, as well as various duplicate and blank samples, and reported the obtained
values in the assay certificates. The SRMs covered a wide range of values, with
certified values as follows: OxA59, 0.0811 g/t Au; OxD57, 0.413 g/t Au; SJ-32, 2.645
g/t Au; and OxL-34 (wrongly reported as SJ-34), 5.758 g/t Au17. ALS also used SRMs
for AuCN, Cu and CuCn. AMEC reviewed the internal ALS QC data from all 2008
Kinross batches, and confirmed that the QC samples (SRMs, duplicates and blanks)
were within acceptable target ranges.
In spite of the lack of detailed information on the geological QC for the 2006 campaign,
assaying was accompanied by a consistent laboratory QC protocol. The 2008
campaign was covered by thorough geological and laboratory QC protocols. AMEC is
of the opinion that these facts permit using the Kinross assay data for resource and
reserve estimation.
14.6.5
Orosur QC 2010
As per the reviewed database, the Orosur QC protocol included the insertion of 425
control samples for 2,925 ordinary samples, as follows: 83 twin (and field duplicate)
samples (2.8% average insertion rate), 185 pulp duplicates (6.3% average insertion
rate), 99 coarse blanks (2.6% average insertion rate), and 80 reference material
samples belonging to four SRMs prepared by CDN (2.7% average insertion rate).The
program did not include the resubmission of check samples to a secondary laboratory.
AMEC processed the Orosur 2010 QC data. The twin sample error rates were 6.0%
for Au and 1.2% for Cu (Table 14-6; Figures 14-2 and 14-3). The pulp duplicate error
rates were 3.8% for Au and 5.9 for Cu% (Table 14-6; Figures 14-4 and 14-5). The
acceptable duplicate error rate is 10%. Therefore, AMEC is of the opinion that the
sampling and analytical variances were within acceptable limits.
17. www.rocklabs.com/reference_material.html
Project No. 3107
October, 2010
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Orosur Mining Inc.
Table 14-6:
Orosur 2010 Campaign: Duplicate Summary
Type
Element
Count
Au
Cu
Au
Cu
Twin Samples/Field
Duplicates
Pulp Duplicates
83
185
Failures
Error Rate (%)
5
1
7
11
6.0
1.2
3.8
5.9
Figure 14-2: Orosur 2010 Campaign Au in Twin Samples and Field Duplicates
Orosur 2010 Exploration: Au in Twin Samples 3.0
2.5
Max Au (g/t)
2.0
Max vs Min
1.5
Failure Line
x = y
Failures
1.0
0.5
0.0
0.0
Project No. 3107
October, 2010
0.5
1.0
1.5
Min Au (g/t)
Page 14-13
2.0
2.5
3.0
Orosur Mining Inc.
Figure 14-3: Orosur 2010 Campaign Cu in Twin Samples and Field Duplicates
Orosur 2010 Exploration: Cu in Twin Samples
0.2
Max Cu (%)
0.2
Max vs Min
Failure Line
0.1
x=y
Failures
0.1
0.0
0.0
0.1
0.1
0.2
0.2
Min Cu (%)
Figure 14-4: Orosur 2010 Campaign Au in Pulp Duplicates
3.5
Orosur 2010 Exploration: Au in Pulp Duplicates
3.0
Max Au (g/t)
2.5
2.0
Max vs Min
Failure Line
x = y
1.5
Failures
1.0
0.5
0.0
0.0
Project No. 3107
October, 2010
0.5
1.0
1.5
2.0
Min Au (g/t)
Page 14-14
2.5
3.0
3.5
Orosur Mining Inc.
Figure 14-5: Orosur 2010 Campaign: Cu in Pulp Duplicates
Orosur 2010 Exploration: Cu in Pulp Duplicates
0.2
Max Cu (%)
0.2
Max vs Min
Failure Line
0.1
x=y
Failures
0.1
0.0
0.0
0.1
0.1
0.2
0.2
Min Cu (%)
All SRM assays were in control, with no outliers being identified. The bias values for
Au ranged between -1.1% and 3.5%, and for Cu between 1.3% and 1.5% (Table 14-7).
The overall bias was -3.9% for Au and -1.1% for Cu (Figures 14-6 and 14-7,
respectively). Consequently, AMEC is of the opinion that the analytical accuracy for Au
and Cu at ACME was high-quality.
All blanks exhibited grades lower than two times the detection limit; hence, no
significant contamination was detected during preparation.
Table 14-7:
SRM ID
CM-5
CGS-19
GS-1E
CGS-P5B
SRM ID
CGS-19
CM-5
Project No. 3107
October, 2010
Orosur 2010 Campaign SRM Summary
Element
Au
Element
Cu
Mean
(g/t)
0.303
0.732
1.161
3.208
BV
(g/t)
0.294
0.740
1.160
3.100
Count
Outliers
21
20
20
19
0
0
0
0
Mean
(%)
BV
(%)
Count
0.134
0.323
0.132
0.319
20
21
Page 14-15
Bias
(%)
3.1
-1.1
0.1
3.5
Overall
Bias (%)
Outliers
Bias
(%)
Overall
Bias (%)
0
0
1.5
1.3
-1.1
-3.9
Orosur Mining Inc.
Figure 14-6: Orosur 2010 Campaign Au Accuracy Plot
Orosur 2010 Exploration: Au Accuracy Plot
3.5
CGS-P5B
3.0
2.5
Mean Au (g/t)
Mean vs BV
2.0
Regresion Line
1.5
y = 0.9606x + 0.0258
R² = 0.9998
GS-1E
1.0
Overall Bias: ‐3.9%
CGS-19
0.5
CM-5
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Best Value Au (g/t)
Figure 14-7: Orosur 2010 Campaign Cu Accuracy Plot
Orosur 2010 Exploration: Cu Accuracy Plot
0.35
CGS-19
0.30
0.25
Mean vs BV
Mean Cu (%)
0.20
Regresion Line
0.15
CM-5
y = 0.9894x - 0.0006
R² = 1
0.10
Overall Bias: ‐1.1%
0.05
0.00
0.00
0.05
0.10
0.15
0.20
0.25
Best Value Cu (%)
Project No. 3107
October, 2010
Page 14-16
0.30
0.35
Orosur Mining Inc.
As a result of the QC data processing, AMEC is of the opinion that the Orosur assay
database is sufficiently precise and accurate for mineral resource estimation purposes.
However, AMEC recommends that during future campaigns the geological QC
protocol be completed with the insertion of coarse duplicates and fine blanks, and with
the submission of check assays to a secondary laboratory.
14.7
Density Review
The density database includes 235 determinations conducted by AA and Kinross on
11 cm to 27 cm core fragments (19 cm on average), apparently using the water
displacement method; however, details about the determination methods were not
available to AMEC.
During the 2010 campaign, Orosur submitted 154 samples for density determination to
ACME. The G8SG method of water displacement method with paraffin coating was
used on 6 cm to 30 cm core fragments (17 cm on average).
All density samples (AA, Kinross and Orosur) were classified by rock type and
according to the mineralization type, as follows: MET (weathered), OX (oxide), MIX
(mixed) and SULF (sulphide). A bulk density summary is presented in
The bulk density of the weathered rock types is significantly lower than the other rock
types, oxide, mixed and sulphide mineralization types are progressively more dense,
and a correlation between sample depth and density exists. These relationships are
all natural consequences of the weathering process and seem to be the most
important controls on bulk density for the Pantanillo deposit (Figure 14-8).
AMEC is of the opinion that Orosur used a proper density determination method, and
that a reasonable quantity of determinations have been made for each major lithology
and mineralization type. However, AMEC recommends that during the future drilling
campaigns additional density samples be obtained, so that the density coverage is
improved.
Project No. 3107
October, 2010
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Orosur Mining Inc.
Table 14-8:
Bulk Density Summary
Rock Type
AA/Kinross
Nr. of
Average Density
3
Samples*
(g/cm )
2.19
2.42
2.49
2.59
MET
OX
MIX
SULF
Total
Orosur
Overall
Average
Nr. of
Average
Density
Samples Density
(g/cm3)
(g/cm3)
2.14
43
2.15
2.38
46
2.40
2.45
62
2.47
**
3
2.59
154
23
37
84
91
235
*: Some samples (13) were not categorically classified;** This average is not considered reliable due to the small
number of samples involved.
Figure 14-8: Bulk Density vs. Depth for Major Rock Types
Pantanillos Project
Density versus Depth Plot
3.00
2.50
Density (g/cm3)
2.00
Met
OX
1.50
MIX
SULF
1.00
0.50
0.00
0
50
100
150
200
250
300
350
Depth (m)
Project No. 3107
October, 2010
Page 14-18
400
450
500
Orosur Mining Inc.
15.0
ADJACENT PROPERTIES
The nearest exploration or mining properties are the Volcán property, belonging to
Andina Minerals (Andina), which is located 11 km northwest of the Property, and the
Refugio mine and the Lobo-Marte properties, located 24 km south-west and 28 km
north of the Property, respectively, both belonging to Kinross. However, none of them
are adjacent to the Property.
Project No. 3107
October, 2010
Page 15-1
Orosur Mining Inc.
16.0
MINERAL PROCESSING AND METALLURGICAL TESTING
The Technical Report on the Pantanillo Project, Region III, Atacama, Chile, dated 14
November 2009 (Siddeley 2009), was reviewed. No additional testwork has been
completed since this report, although more testwork is currently in progress at ACME
to determine the cyanide-soluble gold content from pulp samples. The back-up reports
used in the preparation of the Technical Report were also reviewed. The conclusions
reached by Siddeley (2009) are still valid, and are summarized below.
In 2006 Kinross contracted SGS-Lakefield of Santiago to undertake 10 bottle-roll tests
of drill chips on eight samples (with two duplicates) divided into two size groups, -10
mesh and -200 mesh. The results were clearly for orientation purposes, since the drillchip material did not represent the much coarser heap-leach size, and the laboratory
recoveries obtained therefore might be expected to be considerably better than actual
heap leach recoveries.
Of the eight samples, one was from an oxide-breccia at 110 m depth, one from a
mixed “ore” (oxide/sulphide porphyry) at unknown depth, and the remaining six from a
sulphide-bearing (hypogene) porphyry at various drill depths between 156 m and 460
m.
The gold recovery for the oxide-breccia was 89.6%; the mixed oxide/sulphide sample
gave 62.5% recovery, and the six sulphide samples averaged only 36.6% recovery.
The estimated cyanide consumption was 3.61 kg/t for the oxide material, 4.68 kg/t for
the mixed “ore”, and between 1.4 to 7.1 kg/t for the sulphide material. In all samples
virtually all of the gold was recovered within the first 24 hours.
According to Julian Ford (personal communication, 10 October 2010), recent
investigations by Orosur have shown that cyanide consumption is materially affected
by the pH control and conditioning of samples prior to cyanide leaching. These
passivation characteristics have also been prevalent in some neighbouring properties.
Orosur is currently carrying out detailed investigation relating to both cyanide
consumption and gold recoveries from the various lithological resource zones (La
Cerda, 2010).
From petrological studies, SGS-Lakefield reported that the mixed “ore” had 68% of the
gold in free form, 15% as acid-soluble, 16% in sulphides, and 1% in “locked” silicates
(unrecoverable). Of three sulphide samples studied, the average amount of free gold
was 31%, acid soluble at 27%, 38% in sulphides, and 4% locked in silicates. No
breakdown for the oxide sample was given, although the free-gold content would be
expected to be higher than the 68% reported for the mixed “ore”. Silver, reporting only
Project No. 3107
October, 2010
Page 16-1
Orosur Mining Inc.
trace amounts in the rock, had very poor recoveries (8-10%) and from 24% to 58%
appears to be locked in silicates.
The orientation samples indicated that the Pantanillo oxide could be highly amenable
to cyanide leaching, as might be expected. The sulphide zones gave poor cyanide
leach results and the mixed “ores” were in-between. It should be noted that the
recoveries may have been partially influenced by the “head grade” of the samples
which was higher in the oxide and mixed material (1.4 g/t and 1.8 g/t Au, respectively)
than in the sulphide samples (average 0.78 g/t Au).
The orientation studies pointed to the need to obtain more representative samples,
especially from the oxide zone, where any initial mining activity would be focused, and
from where the best gold recoveries would be expected.
This was addressed by Kinross in the 2008 season, when 1,298 samples were
processed in bottle roll tests. The results are summarized in Table 16-1 (from a
Kinross 2008 exploration summary).
Table 16-1:
Summary of Bottle-Roll Tests (Source: Kinross)
Grade Bracket
(g/t Au)
Above 1.2
1.00 – 1.2
0.8-1.0
0.6-0.8
0.4-0.6
0.2-0.4
0.1-0.2
Project No. 3107
October, 2010
Average Au
Recovery
(%)
79
75
71
65
66
66
70
N° of Samples
Cu
(ppm)
CNCu
(%)
130
48
69
149
274
438
190
416
350
356
302
343
382
229
15
20
16
16
16
18
17
Page 16-2
Orosur Mining Inc.
17.0
MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES
Based upon lithologic, mineralization and alteration interpretations completed by
Orosur, AMEC generated a mineral resource model and estimated mineral resources
for the Property. AMEC estimated gold, total copper and arsenic grades using the
Ordinary Kriging (OK) estimation method, and tabulated the resources within a LerchsGrossman (LG)-optimized pit shell. The economic parameters used to define the
open-pit shell were obtained from benchmark analyses of similar projects in Chile.
This is the first NI 43-101-compliant resource estimation completed for the Property.
17.1
Definitions
Stated mineral resources are derived from estimated quantities of mineralized material
recoverable by established or tested mining methods.
The Pantanillo Norte mineral resource estimate was prepared by Francisco Castillo,
AMEC Senior Modeller, under the supervision of Mrs. Paula Larrondo, AMEC Principal
Geostatistician.
There are numerous inherent uncertainties in the estimation of mineral resources. The
accuracy of the mineral resource estimation is a function of the quality of available
data and of engineering and geological interpretation and judgment. Results from
drilling, testing and production, as well as material changes in gold prices subsequent
to the date of the estimate may justify the revision of such estimates.
17.2
Drilling Database
Orosur provided AMEC with a Microsoft Excel® database containing all drilling
information on the Property.
AMEC imported the collar, survey, lithological,
mineralization and assay data into GEMS® (version 6.22). GEMS®’s validation
routines were used to check for overlapping intervals, missing intervals, and consistent
drill-hole lengths between tables, and no errors were reported.
A total of 20,531 m of drilling in 78 drill holes have been completed at the Property.
Table 17-1 includes a summary of the drill holes that were used for the mineral
resource estimate.
Project No. 3107
October, 2010
Page 17-1
Orosur Mining Inc.
Table 17-1:
Summary of Drill Data Used for the Pantanillo Mineral Resource Estimate
Campaign
Nr. Holes
Minimum
Length (m)
Maximum
Length (m)
Average
Length (m)
Total
Length
(m)
Anglo 1988
5
157
247
227.6
1,138
EMMB 1997-1998
22
138
250
219,3
4,825
Kinross 2006
11
192
700
367.0
4,037
Kinross 2008
10
427
540
489.2
4,892
Pantanillo 2010
30
30.5
266.8
187.9
5,638
Total
78
30.5
700
263.2
20,531
Seven Anglo and Kinross drill holes were not used for mineral classification purposes
at the Property because of uncertainty regarding the collar location (DDHPN01,
DDHPN02, DDHPN03, DDHPN05, DDHPN06, DDH-PN-10 and DDH-PN-16).
AMEC received a digital topography from Orosur in the form of 5 m- and 10 m-spaced
contour lines that were the product of photo-interpretation. AMEC imported the
contour lines into GEMS® and compared the surveyed drill-hole collar elevations
against the topographic surface, and found that significant differences did occur for all
drill holes (Figure 17-1)
Figure 17-1: Difference between Topography versus Collar Elevation
Differences range from -9.7 m to 25.0 m, with 60% of the differences above 10 m,
which is the height of a block. AMEC updated portions of the topographic surface
using surveyed drill-hole collar elevations as a preliminary fix; however, AMEC
Project No. 3107
October, 2010
Page 17-2
Orosur Mining Inc.
recommends that a new digital topographic surface be generated to correct this
problem.
17.3
Geological Model and Definition of Domains
AMEC was provided with vertical sections with interpreted models representing the
Pantanillo Norte lithologic, mineralization, grade-shell and alteration domains. AMEC
digitized the models from the vertical sections and prepared level plans for the grade
shell. Sections were oriented at 011° azimuth (NNE) and spaced 50 m apart. Bench
plans were created at 50 m intervals.
AMEC reconciled the interpreted shapes on vertical sections and level plans, and
constructed solid models for the main lithological units: breccia ledge (BXG), intrusive
breccia (BXI), and andesitic porphyry (VAN_PO). AMEC did not complete a new
interpretation for the lithologic model, but constructed more robust lithologic solids
based upon the reconciled vertical sections and level plans. Similarly, solids for
mineralization units were constructed for leached (MET), oxide (OXI), mixed (MIX),
sulphide (SUL) mineralization units, as well as a 300 ppb grade shell. Alteration solids
were not created at this time, as the interpreted sections needed additional refinement
for conceptual reasonableness.
The lithologic, mineralization and grade-shell solids provided the support for the
estimation domains. Table 17-2 summarizes the lithologic domains used for modeling.
The three-dimensional block model was coded for lithology, mineralization and grade
shell using the solids for each. Sub-blocks were coded on a whole block basis based
upon the centroid location. Later, the sub-block model was regularized, and estimation
was done based on the percentage of the block within the grade shell.
Table 17-2:
Domain
BXG
BXI
VAN_PO
Lithological Unit Description
Description
Ledge breccia (main host rock for mineralization)
Intrusive breccia
Andesitic porphyry
In order to validate the three-dimensional lithologic model, AMEC back-tagged drill
holes with the lithology solids and compared the total length of each domain from the
original logs to the total length obtained from the interpreted model. Results are
summarized in Table 17-4. It is AMEC’s opinion that the differences are acceptable for
this level of study.
Project No. 3107
October, 2010
Page 17-3
Orosur Mining Inc.
Table 17-3:
Comparison of Lithogical Model to Logged Lithology
Unit
Length
(m)
BXG
BXI
VAN_PO
Total
1.086
4,489
10,377
15,953
Original Log
Proportion
(%)
Length
(m)
7
28
65
100
Lithological Model
Proportion
(%)
1.199
4,647
10,106
15,953
8
29
63
100
AMEC defined the estimation domains using the lithology, mineralization and gradeshell three-dimensional models. Gold, copper and arsenic estimation domains were
based on the combination of lithology and mineralization domains, inside and outside
the grade shell (Tables 17-5 to 17-7). The combinations were obtained based on
cumulative probability distributions, basic statistics and contact analysis.
Table 17-4:
Definition of Estimation Domains - Gold
Estimation Domain
Grade Shell
Mineralization
Lithology
UE1
OUT
MET
BXG
UE2
OUT
MET
BXI+VOL
UE3
OUT
OXI+MIX+SUL
ALL
UE4
IN
ALL
ALL
Table 17-5:
Definition of Estimation Domains - Copper
Estimation Domain
Grade Shell
Mineralization
Lithology
UE1
OUT
ALL
ALL
UE2
IN
MET
ALL
UE3
IN
OXI
ALL
UE4
IN
MIX+SULF
ALL
Project No. 3107
October, 2010
Page 17-4
Orosur Mining Inc.
Table 17-6:
17.4
Definition of Estimation Domains - Arsenic
Domain Estimation
Grade Shell
Mineralization
Lithology
UE1
OUT
ALL
BXG
UE2
OUT
MET+OXI+MIX
BXI+VOL
UE3
OUT
SUL
BXI+VOL
UE4
IN
ALL
BXG
UE5
IN
ALL
BXI+VOL
Composites
The nominal sample length for assays was 2 m, corresponding to 82.6% of total
samples; 17.0% of the samples are less than 2 m long, and only 0.4% of the samples
are longer than 2 m. For estimation, the original assayed interval length was used to
honor the grade-shell contacts and variability observed in the deposit.
AMEC back-tagged the samples using the lithology, mineralization and grade-shell
solids for the exploratory data analysis and subsequent grade estimation.
17.5
Exploratory Data Analysis
17.5.1
Basic Statistics
AMEC prepared summary sample statistics for gold, copper and arsenic by lithologic
and mineralization units inside and outside the grade shell. Statistics are summarized
in Tables 17-8 through 17-25. A description of the lithology codes is presented in
Table 17-3.
Table 17-7:
Sample Statistics for Gold Assays by Lithological Unit
Lithology
No. Samples
Min. Au
(ppb)
Max. Au
(ppb)
Mean Au
(ppb)
Standard
Deviation
(ppb)
Coefficient
of Variation
BXG
BXI
VAN_PO
741
3,889
6,242
6
5
5
10,600
4.500
8,611
483
328
352
724
421
529
1.5
1.3
1.5
Project No. 3107
October, 2010
Page 17-5
Orosur Mining Inc.
Table 17-8:
Lithology
BXG
BXI
VAN_PO
Table 17-9:
Lithology
BXG
BXI
VAN_PO
Sample Statistics for Copper Assays by Lithological Unit
No. Samples
Min Cu
(ppm)
Max. Cu
(ppm)
Mean Cu
(ppm)
Standard
Deviation
(ppm)
Coefficient
of Variation
349
1,553
2,917
3
3
2
5,030
5,220
2,310
189
179
168
499
306
203
2.6
1.7
1.2
Sample Statistics for Arsenic Assays by Lithological Unit
No. Samples
Min. As
(ppm)
Max. As
(ppm)
Mean As
(ppm)
Standard
Deviation
(ppm)
Coefficient
of Variation
254
806
2,272
10
6
6
862
1,276
1,599
226
134
147
156
162
158
0.7
1.2
1.1
Table 17-10: Sample Statistics for Gold by Lithological Inside Grade Shell
Lithology
BXG
BXI
VAN_PO
No. Samples
Min. Au
(ppb)
Max. Au
(ppb)
Mean Au
(ppb)
Standard
Deviation
(ppb)
Coefficient
of Variation
243
1,249
1,915
70
24
45
10,600
4,500
8,611
852
691
819
936
554
713
1.1
0.8
0.9
Table 17-11:Sample Statistics for Copper by Lithological Inside Grade Shell
Lithology
BXG
BXI
VAN_PO
No. Samples
Min. Cu
(ppm)
Max. Cu
(ppm)
Mean Cu
(ppm)
Standard
Deviation
(ppm)
Coefficient
of Variation
112
492
909
9
14
17
2,600
4,778
2,310
238
329
273
358
361
267
1.5
1.1
1.0
Table 17-12:Sample Statistics for Arsenic by Lithological Inside Grade Shell
Lithology
BXG
BXI
VAN_PO
Project No. 3107
October, 2010
No. Samples
Min. As
(ppm)
Max. As
(ppm)
Mean As
(ppm)
Standard
Deviation
(ppm)
Coefficient
of Variation
92
303
705
15
6
6
757
1,276
1,501
278
151
168
176.02
151.44
163.32
0.6
1.0
1.0
Page 17-6
Orosur Mining Inc.
Table 17-13: Sample Statistics for Gold by Lithological Outside Grade Shell
Lithology
BXG
BXI
VAN_PO
No. Samples
Min. Au
(ppb)
Max. Au
(ppb)
Mean Au
(ppb)
Standard
Deviation
(ppb)
Coefficient
of Variation
439
2,586
4,235
6
5
5
4,700
2,500
3,380
265
157
139
439.56
157.96
175.96
1.7
0.8
1.3
Table 17-14: Sample Statistics for Copper by Lithological Outside Grade Shell
Lithology
BXG
BXI
VAN_PO
No.
Samples
Min. Cu
(ppm)
Max. Cu
(ppm)
Mean Cu
(ppm)
Standard
Deviation
(ppm)
Coefficient
of
Variation
218
1,043
1,968
3
3
2
5,030
5,220
1,840
152
114
119
512.48
266.78
140.65
3.4
2.3
1.2
Table 17-15: Sample Statistics for Arsenic by Lithological Outside Grade Shell
Lithology
BXG
BXI
VAN_PO
No.
Samples
Min. As
(ppm)
Max. As
(ppm)
Mean As
(ppm)
Standard
Deviation
(ppm)
Coefficient
of
Variation
156
498
1,538
10
6
7
862
1,276
1,599
194
124
137
133
167
154
0.7
1.3
1.1
Table 17-16: Sample Statistics for Gold by Mineralization Inside Grade Shell
Mineralization
Leach
Oxi
Mix
Sul
No.
Samples
Min. Au
(ppb)
Max. Au
(ppb)
Mean Au
(ppb)
Standard
Deviation
(ppb)
Coefficient
of
Variation
427
1,121
1,086
773
24
45
81
55
8,611
8,480
10,600
4,500
773
843
772
683
665
720
725
550
0.9
0.9
0.9
0.8
Table 17-17: Sample Statistics for Copper by Mineralization Inside Grade Shell
Leach
300
9
1,966
212
Standard
Deviation
(ppm)
274
Oxi
Mix
Sul
505
527
181
21
18
32
1,785
4,778
2,600
243
355
314
219
388
263
Mineralization
Project No. 3107
October, 2010
No.
Samples
Min. Cu
(ppm)
Max. Cu
(ppm)
Page 17-7
Mean Cu
(ppm)
Coefficient
of Variation
1.3
0.9
1.1
0.8
Orosur Mining Inc.
Table 17-18: Sample Statistics for Arsenic by Mineralization Inside Grade Shell
Mineralization
Leach
Oxi
Mix
Sul
No.
Samples
Min. As
(ppm)
Max. As
(ppm)
MeanAs
(ppm)
298
406
389
7
13
17
6
23
1,501
1,245
1,223
172
201
169
159
67
Standard
Deviation
(ppm)
161
154
174
45
Coefficient
of
Variation
0.8
0.9
1.1
0.7
Table 17-19: Sample Statistics for Gold by Mineralization Outside Grade Shell
Mineralization
Leach
Oxi
Mix
Sul
No.
Samples
1,919
1,567
2,410
1370
Min.Au
(ppb)
5
5
5
5
Max.
Au
(ppb)
4,700
2,830
2,500
1,650
Mean
Au
(ppb)
136
154
165
157
Standard
Deviation
(ppb)
251
202
164
168
Coefficient
of
Variation
1.8
1.3
1.0
1.1
Table 17-20: Sample Statistics for Copper by Mineralization Outside Grade Shell
Mineralization
Leach
Oxi
Mix
Sul
No.
Samples
Min.Cu
(ppm)
Max.Cu
(ppm)
MeanCu
(ppm)
Standard
Deviation
(ppm)
Coefficient
of
Variation
1,071
805
945
411
2
3
3
3
3,132
3,484
5,220
891
96
142
146
82
149
247
327
110
1.6
1.7
2.2
1.3
Table 17-21: Sample Statistics for Arsenic by Mineralization Outside Grade Shell
No.
Samples
Leach
Oxi
Mix
Sul
Project No. 3107
October, 2010
809
599
742
42
Min As
(ppm)
Max. As
(ppm)
7
8
6
44
Page 17-8
1,599
815
1,446
744
Mean As
(ppm)
Standard
Deviation
(ppm)
162
131
113
220
188
126
136
160
Coefficient
of
Variation
1.2
1.0
1.2
0.7
Orosur Mining Inc.
Table 17-22: Sample Statistics for Gold by Domains
Domains
EU1
EU2
EU3
EU4
No.
Samples
Min.
Au
(ppb)
254
1,665
5,756
243
6
5
5
70
Max. Au
(ppb)
Mean Au
(ppb)
4,700
3,380
5,430
10,600
Standard
Deviation
(ppb)
278
114
152
852
496
175
204
936
Coefficient
of
Variation
1.8
1.5
1.0
1.1
Table 17-23: Sample Statistics for Copper by Domains
Domains
EU1
EU2
EU3
EU4
No.
Samples
Min. Cu
(ppm)
Max. Cu
(ppm)
Mean Cu
(ppm)
Standard
Deviation
(ppm)
Coefficient
of
Variation
3,430
300
505
708
1
9
21
18
5,220
1,966
1,785
4,778
112
212
243
343
228
274
219
358
2.0
1.3
0.9
1.0
Table 17-24: Sample Statistics for Arsenic by Domains
Domains
EU1
EU2
EU3
EU4
EU5
No.
Samples
156
1,994
42
92
1008
Min. As
(ppm)
10
6
44
15
6
Max. As
(ppm)
862
1,599
744
757
1,501
Mean As
(ppm)
194
132
220
278
162
Standard
Deviation
(ppm)
133
157
151
161
160
Coefficient
of
Variation
0.7
1.2
0.7
0.6
1.0
AMEC constructed box plots for gold, copper and arsenic assays (Figure 17-2 through
Figure 17-7). The box plots illustrate the gold, copper and arsenic distributions for the
different lithologic and domain units. AMEC observed that the BXG unit has the
highest gold mean, and that the BXI unit has a lower coefficient of variation (CV) than
other lithologies with more homogenous distributions.
Project No. 3107
October, 2010
Page 17-9
Orosur Mining Inc.
Figure 17-2: Box Plot for Gold Assays
The copper box plots display different distributions between the lithology units. The
BXG unit is preferentially mineralized, with a higher mean in both copper and gold, but
it also has a higher CV for copper.
Project No. 3107
October, 2010
Page 17-10
Orosur Mining Inc.
Figure 17-3: Box-Plot for Copper Assays
Figure 17-4: Box Plot for Arsenic Assays
Project No. 3107
October, 2010
Page 17-11
Orosur Mining Inc.
Figure 17-5: Box Plot for Gold Domains
Figure 17-6: Box Plot for Copper Domains
Project No. 3107
October, 2010
Page 17-12
Orosur Mining Inc.
Figure 17-7: Box Plot for Arsenic Domains
AMEC also calculated cumulative-frequency distributions and histograms for gold,
copper and arsenic for lithologic, mineralization, grade-shell and estimation domains.
Figure 17-8 illustrates the gold cumulative-frequency distribution for the BXG unit.
In general, the summary statistics show higher gold and copper grades in the BXG
unit; however, high grades in the deposit are not confined only to this unit, and the
lithology and mineralization interpreted models solely are not enough to explain the
gold grade distribution. Because of this, a grade shell at 300 ppb Au had to be used to
constrain grade estimation. Orosur’s interpreted grade shell was refined using an
indicator estimation for that cutoff, as an effort to consistently define a volume of
influence for grades above the cutoff in areas with less drilling density.
Project No. 3107
October, 2010
Page 17-13
Orosur Mining Inc.
Figure 17-8: Cumulative Frequency Distribution for Gold - BXG unit (Assays)
17.5.2
Contact Analysis
AMEC constructed contact profiles to analyze the grade behaviour at the lithology,
mineralization and grade-shell boundaries. The analysis defined hard and soft
contacts, both of which are important for the grade-estimation plan: soft contacts
permit sample sharing from two adjacent lithology units during the grade estimation,
whereas hard contacts do not permit sample sharing.
The analysis was completed for gold, copper and arsenic values. Similar results were
observed for these elements. Figure 17-9 shows an example of a contact plot between
the BXG and BXI units. The contacts between estimation domains were considered to
be hard for grade estimation purposes, due to the change in average grade across the
boundaries.
Project No. 3107
October, 2010
Page 17-14
Orosur Mining Inc.
Figure 17-9: Contact Plot for Gold BXG - BXI
17.6
Variography
AMEC used the Sage2001 software to construct down-the-hole and directional
correlograms for the gold, copper and arsenic estimation units. The correlograms show
good continuity in the orientation of the mineralized body, striking approximately 125°
azimuth and dipping 60° southwest. This orientation is similar to that exhibited by the
BXG breccias, and suggests a structural control on mineralization distribution that
should be further investigated and incorporated in future models.
17.7
Restriction of Extreme High-Grade Values
AMEC used the cumulative probability distribution by estimation domain to define
grade outliers. Outlier values can impact the grade estimation through the smearing of
anomalous high grades, and subsequently cause grade overestimation. Figure 17-10
shows gold distribution by estimation domains.
Project No. 3107
October, 2010
Page 17-15
Orosur Mining Inc.
Figure 17-10: Probability Plots Au-Domains
AMEC applied outlier restriction using a restricted search ellipsoid; grades above the
threshold were only used if they occur within the restricted ellipsoid. The grade and
distance thresholds for the outlier restriction were defined for gold, copper and arsenic
by estimation units, and are summarized in the estimation plan (Tables 17-27 through
17-29).
17.8
Block-Model Dimensions and Grade Estimation
The block model consists of regular blocks (10 m x 10 m x 10 m) and is rotated at
11.12o azimuth (Table 17-25).
Table 17-25: Block Model Dimensions
Coordinate
Minimum
Maximum
Block Dimensions
(m)
(m)
(m)
10
Number of Blocks
Easting
493,001.151
493,165.086
Northing
6,964,410.74
6,965,244.782
10
95
Elevation
3,900
4,700
10
80
Project No. 3107
October, 2010
Page 17-16
85
Orosur Mining Inc.
17.8.1
Estimation Plan
AMEC estimated gold, copper and arsenic grades by estimation domains using
ordinary kriging (OK) estimation. The grade estimation was completed in three
passes. The estimation parameters are summarized in Table 17-26 through Table 1728. In Table 17-28, hard contacts were assumed, so that samples were not shared
across boundaries.
AMEC defined a single-search orientation for all domains based upon geological
trends and grade continuity observed from the visual inspection of drill-hole data.
AMEC estimated the grade inside and outside the grade shell; samples were selected
according to their position with respect to the grade-shell, lithology and mineralization
units.
At the boundary of the grade shell, the proportion of the block within and outside the
grade shell was considered for gold estimation. The final gold estimation was the
combination of gold estimated outside the grade shell with samples of EU1, EU2 or
EU3 (Au1), and a gold grade estimated inside the grade shell with the samples of EU4
(Au2), depending on the mineralization and lithology of the block. These two estimates
were combined based on the proportion of the block inside and outside the grade
shell, as an effort to consider geological dilution at this hard boundary.
Project No. 3107
October, 2010
Page 17-17
Orosur Mining Inc.
Table 17-26: Estimation Parameters for Gold
Search Ellipsoid
Domain
EU1
EU2
EU3
EU4
Pass
1
2
3
1
2
3
1
2
3
1
2
3
Rotation (°)
High-Grade Search Radii
Range (m)
Bearing
Plunge
Dip
Major
SemiMajor
Minor
Grade
Limits
(ppm)
35
35
35
35
35
35
35
35
35
35
35
35
60
60
60
60
60
60
60
60
60
60
60
60
0
0
0
0
0
0
0
0
0
0
0
0
60
120
180
60
120
180
60
120
180
60
120
180
60
120
180
60
120
180
60
120
180
60
120
180
30
60
90
30
60
90
30
60
90
30
60
90
650
650
650
520
520
520
800
800
800
4,500
4,500
4,500
Range (m)
Major
SemiMajor
Minor
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
Min.
No.
Samples
Max. No.
Samples
Samples
per Hole
24
24
24
24
24
24
24
24
24
24
24
24
48
48
48
48
48
48
48
48
48
48
48
48
12
12
Min.
No.
Samples
Max. No.
Samples
Samples
per Hole
12
12
12
12
12
12
Table 17-27: Estimation Parameters for Total Copper
Search Ellipsoid
Domain
EU1
EU2
EU3
EU4
Project No. 3107
October 2010
Pass
Rotation (°)
Range (m)
Range (m)
Bearing
Plunge
Dip
Major
SemiMajor
Minor
Grade
Limits
(ppm)
1
2
3
1
2
3
1
2
3
1
35
35
35
35
35
35
35
35
35
35
60
60
60
60
60
60
60
60
60
60
0
0
0
0
0
0
0
0
0
0
140
280
420
130
260
390
165
330
495
170
120
240
360
100
200
300
60
120
180
80
60
120
180
60
120
180
60
120
180
60
990
990
990
870
870
870
760
760
760
1,200
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
16
16
16
16
16
16
16
16
16
16
32
32
32
32
32
32
32
32
32
32
8
8
2
35
60
0
340
160
120
1,200
15
15
15
16
32
8
3
35
60
0
510
240
180
1,200
15
15
15
16
32
Page 17-18
Major
SemiMajor
Minor
8
8
8
8
8
Orosur Mining Inc.
Table 17-28: Estimation Parameters for Total Arsenic
Search Ellipsoid
Domain
EU1
EU2&EU
3
EU4
EU5
Project No. 3107
October 2010
Pass
Rotation (°)
Range (m)
Range (m)
Min. No.
Sample
s
Max. No.
Samples
Samples
per Hole
Bearing
Plunge
Di
p
Major
SemiMajor
Minor
GradeLi
mits
(ppm)
1
35
60
0
140
130
100
990
15
15
15
16
32
8
2
35
60
0
280
260
200
990
15
15
15
16
32
8
3
35
60
0
420
390
300
990
15
15
15
16
32
1
35
60
0
130
100
60
870
15
15
15
16
32
8
2
35
60
0
260
200
120
870
15
15
15
16
32
8
3
35
60
0
390
300
180
870
15
15
15
16
32
1
35
60
0
165
60
60
760
15
15
15
16
32
8
2
35
60
0
330
120
120
760
15
15
15
16
32
8
3
35
60
0
495
180
180
760
15
15
15
16
32
1
35
60
0
170
80
60
1,200
15
15
15
16
32
8
2
35
60
0
340
160
120
1,200
15
15
15
16
32
8
3
35
60
0
510
240
180
1,200
15
15
15
16
32
Page 17-19
Major
SemiMajor
Minor
Orosur Mining Inc.
AMEC defined an estimation plan for gold in three passes. Pass 1 required a minimum
of two drill holes, a minimum of 24 samples, and a maximum of 48 samples. Pass 2
estimated blocks not previously estimated in Pass 1, and required two drill holes
maintaining the minimum and maximum number of samples for estimating one block,
and increasing to twice the search radii.
17.9
Density
AMEC calculated average density values for each mineralization unit from the density
database provided by Orosur (Figure 17-11). Some determinations were excluded
from the calculations, though, due to apparent inconsistencies (anomalously low
values, confusing classification, etc.). These average values could change as
additional determinations are acquired in the future. AMEC assigned density values to
blocks based upon the mineralization codes as in Table 17-29Figure 17-11: Box Plot for Density
Project No. 3107
October 2010
Page 17-20
Orosur Mining Inc.
Table 17-29: Average Density Values for the Pantanillo Norte Resource Model
Determinations
Density (g/cm3)
Leach
66
2.19
Oxide
81
2.41
Mixed
145
2.47
Sulphide
93
2.59
Rock Type
17.10
Block-Model Validation
AMEC validated the Pantanillo Norte model using summary statistics to check for
global estimation bias, drift analysis, smoothing assessment and visual inspection.
For validation purposes, AMEC generated a nearest neighbour model (NN) using 10 m
composites in order to verify that kriged estimates honoured the drill-hole data. The
NN model provides a declustered distribution of drill-hole data, and is commonly used
for validating the grade estimation.
Basic Statistics
AMEC generated tables of basic statistics comparing the OK and NN estimates to
check for global bias in the gold, copper and arsenic grade estimates (Table 17-30
through Table 17-31). The OK estimate is slightly lower in mean gold grade compared
to the NN estimate for low-grade domains outside the grade shell. The OK grade
estimates for copper are lower than the NN grades. Nevertheless, AMEC has found
these differences to be acceptable.
Table 17-30: Comparison of Composite Statistics with OK and NN Estimates for Gold
Composites
Domain
No.
Mean
(ppb)
EU1
254
277
EU2
1,665
EU3
EU4
Blocks
Mean
CV
CV
No.
OK
(ppb)
NN
(ppb)
OK/NN
(%)
OK
NN
OK/NN
(%)
1.8
1,310
178
194
92
0.2
0.1
131
114
1.6
20,697
167
189
88
0.4
0.3
124
5,757
152
1.4
185,946
217
230
94
0.3
0.4
59
3,164
852
1.1
46,566
739
735
101
0.3
0.6
54
Note: OK, Ordinary Kriging; NN, Nearest Neighbour; CV, coefficient of variation
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Table 17-31: Comparison of Composite Statistics with OK and NN Estimates for Copper
Composites
Domai
n
No.
3,43
0
300
505
708
EU2
EU3
EU4
Blocks
Mean
Mean
(ppm
)
CV
112
2.0
212
243
343
1.3
0.9
1.0
No.
336,44
3
3,343
5,747
35,665
OK
(ppm)
NN
(ppm)
CV
OK/N
N
(%)
OK
NN
OK/N
N
(%)
128
137
83
0.5
1.1
41
166
204
275
187
230
277
89
87
99
0.5
0.4
0.3
1.3
0.9
1.0
39
39
34
Table 17-32: Comparison of Composite Statistics with OK and NN Estimates for Arsenic
Composites
Blocks
Mean
Domain
No.
EU1
156
Mean
(ppm)
CV
194
0.7
5,087
183
250
No.
OK
(ppm)
NN
(ppm)
CV
NN
OK/NN
(%)
0.2
0.4
49
OK/NN
(%)
OK
73
EU2
1,994
132
1.2
243,779
204
345
59
0.6
0.7
86
EU4
92
278
0.6
2,406
242
208
116
0.3
0.8
32
EU5
1008
162
1.0
40,485
159
218
73
0.5
0.8
62
17.10.1 Drift Analysis
A drift analysis was performed for gold, copper and arsenic in the northeast-southwest
direction and benches. Swath-plot validation compared the averaged grades from OK
and NN models in five-block wide (50 m) NW-SE slices and ten-block wide (100 m)
NE-SW slices, and on 25 m high benches. AMEC used only blocks estimated in
Passes 1 y 2 (Table 17-26 through Table 17-28 ) for this analysis. Figure 17-12 and
Figure 17-13 compare the OK and NN estimates by estimation domains on vertical
swath plots for gold.
AMEC observed that all domains display local bias for the gold OK estimate compared
to the NN estimate. Discrepancies at the margins of the model are a result of limited
data. In general, local differences are less than 10%.
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Figure 17-12: Drift Analysis – Au1 in EU1, EU2 and EU3 (NW-SE orientation)
Figure 17-13: Drift Analysis – Au2 in EU4 Domain (NE-SW orientation)
17.10.2 Smoothing
Kriged estimates are generally used directly for estimating resource tonnages above
various cutoffs. This practice gives correct results, a priori, only at a zero-grade cutoff.
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At any cutoff grade that is greater than zero, the smoothing effect may distort the
kriged-estimate grade-tonnage curves. The effective amount of smoothing in the
kriged estimates depends upon the variogram model, in particular the nugget effect
and the ranges, and upon the composite selection criteria used for kriging. At cutoffs
less than the global average grade, the tonnage given by the kriged estimates will be
overestimated, and at cutoffs greater than the global average grade, the tonnage will
be underestimated.
There are several techniques to assess and handle this problem. AMEC traditionally
uses a Hermitian correction method, which consists of:
•
Computing the theoretical dispersion variance of the blocks, knowing the variogram
model of the relevant metals.
•
Transforming the distribution of the declustered composites (NN) so that it reflects a
block support, which is done using a Hermitian correction (Herco).
•
Comparing the grade-tonnage curve of the Herco transforms with the gradetonnage curve of the kriged estimates.
Figure 17-14 shows the comparison of the grade-tonnage curve of the Herco
transforms against kriged estimates for low-gold grade domains combined. The good
agreement between these curves suggests that smoothing is well controlled
(differences are less that 4%).
For the domain inside the grade shell (EU4), smoothing is well controlled as well, with
a global smoothing of 3%. However, for cutoffs between 200 ppb and 800 ppb, the
differences in tonnage can be as high as 4% (Figure 17-15)
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Figure 17-14: Herco Analysis Pantanillo Norte: EU1, EU2, EU3 Domains
Figure 17-15: Herco Analysis Pantanillo Norte: EU4 Domain
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Visual Validation
AMEC completed a visual inspection comparing grades of composites and blocks in
vertical sections and plan views. AMEC concluded that the grade estimate reasonably
represents the assays grades, and that grade extrapolation is well controlled. Figure
17-16 is an example of a vertical section with composites and blocks coloured by gold
ranges. A good agreement of the estimated grades and composites is also observed in
plan view at elevation 4,450 m (Figure 17-17)
AMEC observed local areas with high-grade open areas at depth and towards the
northeast. These areas indicated that the mineralization limits have not yet been
defined by drilling in certain areas. Additional drilling is required to determine the
mineralization limits in some areas, with the possibility of increasing resources.
Figure 17-16: Vertical Section 5NW with Blocks and Assay Grades for Gold (50 m
Corridor).
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Figure 17-17: Plan View at Elevation 4,450 m Showing High-Grade Extrapolation.
17.11
Resource Classification and Tabulation
The resource classification should integrate criteria addressing at least the following
four parameters:
•
Geological continuity of the mineralization (confidence in location, geometry and
thickness between drill holes)
•
Grade continuity
•
Data quality and support (multiple points of support)
•
Reasonable prospects for economic extraction.
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Grade and volume continuity are considered through the use of the kriging
parameters. For the Property, AMEC used the number of drill holes and the average
distance of samples used to estimate a block, as well as the distance of the closest
sample to define Measured, Indicated and Inferred blocks, according to Table 17-23.
Additionally, the number of drill holes and the number of samples used to ensure two
drill holes were considered to estimate blocks classified as Measured (Table 17-26).
The kriging parameters used in the first pass did not ensure that two drill holes be
used in grade estimation.
Table 17-33: Parameters for Open-Pit Resource Classification
Category
Measured
Indicated
Inferred
No. of Drill holes
Distance to Closest Sample
(m)
Average Weighted
Distance (m)
At least two
0 to 50
0 to 75
At least two
50 to 100
75 to 150
No restriction
No restriction
No restriction
Figures 17-18 and Figure 17-19 show resource classification on a vertical section and
plan view, respectively.
Figure 17-18: Section 10NW - Resource Classification
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Figure 17-19: Plan View 4,500m - Resource Classification
As part of data quality considerations for resource classification, seven Anglo and
Kinross drill holes were not used for Measured or Indicated resource classification due
to uncertainty in the location (Section 17-2).
AMEC determined reasonable prospects of economic extraction by applying
preliminary economics for open pit mining methods. Mining and process costs and
process recoveries were estimated from benchmark studies of similar projects and
operations in Chile.
Historical metallurgical data was provided by Orosur. AMEC studied this data and
considered the figures presented as referential, based on the wide range of results
observed and the uncertainty related to the representativeness of this data.
Average gold recoveries for sulphide mineralization from 2006 bottle tests are actually
lower than the recovery value used in this report during pit optimization. The number
and representativeness of the metallurgical tests available to date for sulphide
mineralization are incomplete and the figures of reasonable prospects of economical
extraction of this material are subject of uncertainty in this regard. The gold recovery
value use for sulphide mineralization was based predominantly in benchmark figures
from nearby operations of similar characteristics.
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AMEC recommends that further investigations be develop including sampling
protocols, sample representativeness and a proper metallurgical test plan. This plan
should consider a test battery regarding the reagents consumption, metallurgical
recovery and other elements that could eventually decrease the synergies and
increment reagents consumption. In the Pantanillo particular case, cyanide
consumption, recovery, other cyanide consumers and kinetic of the leaching process,
should be analyzed.
The resource estimate utilized ordinary kriging for grade interpolation. To ensure
reasonable prospects of economic extraction in open pit operations, mineral resources
are reported within a Lerchs-Grossman (LG)-optimized pit shell (Figure 17-20) using
Whittle® software using the parameters listed in Table 17-34.
Table 17-34: Optimization Parameters for Open-Pit Resource Shell
Parameter
Value
45
Slope Angle (°)
Mining Cost (US$/t)
1.65
Mining Dilution Fraction
1
Processing Cost (US$/t) 1
4.0
General and administration cost (US$/t)
1.0
Recoveries for Leached and Oxide (%)
75
Recoveries for Mixed (%)
65
Recoveries for Sulphide (%)
50
Gold Price (US$/oz)
1
1,035
Processing cost is based on heap leach recovery method only
Total Measured and Indicated mineral resources are 47,093 kt at 0.69 g/t gold, for
1,049.1 koz of gold, with a further 304 t at 0.53 g/t gold, for 5.1 koz of gold, in the
Inferred category. The following table presents a breakdown by category of the resource
estimate.
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Table 17-35: Mineral Resources by Mineralization Domains
Ore
Type
Cutoff
Au
(g/t)
Measured
Indicated
Measured + Indicated
Inferred
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
Au
Tonnage
Au Metal
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
(g/t)
(kt)
(oz)
Oxide
0.3
0.72
19,806
456,349
0.55
1,752
30,963
0.70
21,558
487,708
0.39
124
1,558
Mixed
0.3
0.7
16,011
361,246
0.65
8,336
173,619
0.68
24,348
534,865
0.62
180
3,608
0.5
0.72
748
17,328
0.68
440
9,566
0.70
1,187
26,894
0.00
0
0
0.71
36,565
834,924
0.63
10,528
214,148
0.69
47,093
1,049,071
0.53
304
5,166
Sulphide
Total
123
1
Totals may differ slightly from sum or weighted sum of numbers due to rounding.
Copper and arsenic average grades above cutoff are respectively: 0.025% and 144 ppm for Measured plus Indicated and 0.019% and 124 ppm for
Inferred
3
Mineral resources are reported within a Lerchs-Grossman (LG)-optimized pit shell using Whittle® software with a gold price of 1,035 US$/oz; mining
cost of 1.65 US$/t; processing cost of 4.0 US$/t; general and administration cost of 1.0 US$/t, and recoveries of 75% for leached and oxide ore types,
2
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Figure 17-20: Section 5NW Showing the Outline of the Resource Pit
Outside the resource described above, AMEC considers that there is a target for further
exploration of approximately 30 Mt to 40 Mt at a grade of 0.6 g/t to 0.8 g/t Au of
predominantly sulphide mineralization. At this point in time, the potential tonnage and
grade of the exploration target is conceptual in nature, there has been insufficient
exploration to define this target as a mineral resource, and it is uncertain if further
exploration will result in the target being delineated as a mineral resource.
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18.0
OTHER RELEVANT DATA AND INFORMATION
No other relevant data or information has been provided to AMEC that should be
included in this report.
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19.0
ADDITIONAL REQUIREMENTS FOR TECHNICAL REPORT ON
DEVELOPMENT PROPERTIES AND PRODUCTION PROPERTIES
The Pantanillo Property is not a Development or Production Property as defined by NI
43-101.
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20.0
INTERPRETATION AND CONCLUSIONS
20.1
Geology, Exploration and Data Verification
The Pantanillo property lies on the eastern flanks of the Azufre/ Copiapó volcanic
complex, within a mainly dacitic to locally rhyolitic composition, hydrothermally altered
volcaniclastic units. The volcanic sequence was intruded by a flow-dome complex
composed of feldspar-hornblende-(biotite-quartz) porphyritic units with a NW-SEelongated, slightly oval shape covering approximately 2.5 km2.
A series of WNW-ESE (locally NW-SE)-striking, sub-vertical breccia units have been
mapped in the area. These units have pervasive advanced-argillic alteration, exhibit
tabular to locally irregular geometry, and reach up to 50 m in width. The breccias
postdate the formation of the Au-porphyry mineralization, as suggested by the
presence of mineralized porphyry veinlet clasts within the breccia.
Gold mineralization is mainly represented by sheeted-vein sets and weak stockwork
networks of quartz veinlets, which show textures similar to those types documented in
other Au-rich porphyry systems in the Maricunga Belt. Au grade in core intersections
with strong banded-veining intensity commonly range from 1.0 g/t to 4.0 g/t. Quartzalunite ledges are discontinuous and volumetrically restricted, and ledge-hosted Au
mineralization at the Property is highly erratic, although it may locally reach up to 2.5
g/t.
described for the Property: oxide, mixed, and sulphide.
During the 2010 exploration campaign, Orosur drilled 19 DD holes, totalling 3,785 m,
and 11 RC holes, totalling 1,854 m. Industry-standard practices were followed during
surveying, drilling and sampling during the campaign, and a comprehensive QA/QC
program was in place. ACME Santiago was used as primary laboratory.
AMEC reviewed the exploration methods and verified the data obtained during the AA
and Kinross exploration campaigns prior to the Orosur 2010 drilling campaign. The
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available information was partial for the AA and Kinross exploration, and thorough for
the Orosur exploration. As a result of this review, AMEC is of the opinion that:
20.2
•
The regional setting and the local geology of the Property are adequately known to
support mineral resource estimation.
•
Surface and down-hole surveying, diamond and RC drilling, logging and sampling
during the 2010 campaign were conducted according to industry-standard
procedures.
•
The sample preparation and assaying procedures during the Kinross and Orosur
exploration campaigns were adequate for this type of deposits.
•
During the AA and Kinross exploration, Au analytical accuracy was usually within
acceptable limits.
•
During the Orosur exploration, sampling and analytical precision for Au and Cu
were within acceptable limits. Analytical accuracy for Au and Cu can be deemed as
acceptable. Cross-contamination for Au and Cu during preparation and assaying
was not significant.
•
Significant Au decay-related or cyclicity-related down-hole contamination did not
occur during the 2010 exploration campaign.
•
Orosur used a proper density determination method, and the amount of
measurements was sufficiently representative of major lithology and mineralization
types.
•
Survey and down-hole survey data, lithology and alteration data, assay and density
data have been accurately recorded.
•
The geological interpretation generally respects the data recorded in the logs and
the sections, as well as the interpretation from adjoining sections, and is consistent
with the known characteristics of this deposit type.
•
As a result of the review, AMEC is of the opinion that the Pantanillo database can
be used for mineral resource estimation purposes.
Metallurgy
The limited metallurgical studies available on orientation samples indicate that the
Pantanillo oxide mineralization could be amenable to cyanide leaching. The sulphide
mineralization gave poor cyanide leach results and the mixed mineralization results
were moderate.
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20.3
Resource Estimation
•
The lithology and mineralization, especially the HS ledge breccias, are controls of
gold, copper and arsenic distribution in the deposit. However, the interpreted
models solely were not enough to explain the spatial distribution of relatively higher
grades, therefore, a grade shell at 300 ppb Au had to be used to constrain grade
estimation. Estimation domains are based in the combination of lithology,
mineralization and a three-dimension grade shell model.
•
The spatial analysis show good grade continuity in the orientation of the
mineralized body, correlograms were calculated and model in this direction. Search
orientation was set in the same orientation and ordinary kriging was used for grade
estimation.
•
Validation of the block model shows a good global and local agreement between
the OK estimates and the NN model, and smoothing is controlled.
•
Higher-grade mineralization distribution is well constrained in space within the
deposit, and resulted in the objective definition of volume and grade.
•
AMEC classified the mineral resources in the Measured, Indicated and Inferred
categories based on sample number, data quality, drill-hole density and good
variographic fit.
•
To assess reasonable prospects of economic extraction in open pit operations,
mineral resources were reported within a Lerchs-Grossman (LG)-optimized pit shell
using Whittle® software with the following parameters: gold price of 1,035 US$/oz;
mining cost of 1.65 US$/t; processing cost of 4.0 US$/t; general and administration
cost of 1.0 US$/t, and gold recoveries of 75% for leached and oxide ore types,
•
values. For sulphides, AMEC recommends that additional samples be tested for
metallurgy variables, such us recovery, in areas of relatively higher grades in
sulphides to decrease uncertainty of prospects of economical extraction.
•
Outside the resource described above, AMEC considers that there is a target for
further exploration of approximately 30 Mt to 40 Mt at a grade of 0.6 g/t to 0.8 g/t
Au of predominantly sulphide mineralization. At this point in time, the potential
tonnage and grade of the exploration target is conceptual in nature, there has been
insufficient exploration to define this target as a mineral resource, and it is
uncertain if further exploration will result in the target being delineated as a mineral
resource.
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21.0
RECOMMENDATIONS
On the basis of the review and verifications conducted during the preparation of the
Technical Report, AMEC has the following recommendations:
•
The deposit has additional exploration potential for sulphide mineralization in the
deeper horizons. AMEC recommends drilling seven 500 m long drill holes in
sections 3NW, 5NW, 6NW, 7NW, 10NW, 12NW and 16NW (totalling 3,500 m), in
order to delimit the mineralization in depth toward southwest (Table 21-1).
•
AMEC recommends drilling three 500 m deep drill-holes (totalling 1,500 m) in the
south-east portion of the Property, to determine the potential below the ignimbritic
cover (Table 21-1).
•
AMEC recommends drilling six 300 m long infill holes in the high-grade portion of
the deposit to increase the mineral resource classification and to provide
•
AMEC recommends drilling two 500 m long drill holes to test for the presence of
additional porphyry systems on the Property.
•
During future drilling campaigns, the geological QC protocol should be completed
with the insertion of coarse duplicates and fine blanks, and with the submission of
check assays to a secondary laboratory in adequate proportions.
•
In future drilling campaigns, it is recommended that 5% of the RC holes be twinned
by diamond drill holes, including three drill holes from pre-Orosur exploration
campaigns.
•
Orosur should continue to enlarge the density database with new determinations.
•
A new digital topographic surface should be generated to correct the observed
differences between the collar elevations and the current digital topographic
surface.
•
Additional controls of gold distribution, such as a structural control on
mineralization should be investigated and incorporate in future models. The
mineralized body is well constrain spatially but the lithology and mineralization
interpreted models are not enough to explain the occurrence of relatively higher
grades in the deposit.
•
Further investigations should be developed to decrease uncertainty in the recovery
values use in this study to determined reasonable prospects of economic
extraction of mineral resource. A metallurgical test plan, including sampling
protocols, sample representativeness and a test battery regarding the reagents
consumption, metallurgical recovery and other elements that could eventually
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decrease the synergies and increment reagents consumption, in particular, cyanide
consumption, recovery, other cyanide consumers and kinetic of the leaching
process, should be analyzed.
•
AMEC anticipates that 8,700 m of drilling will be required in order to accomplish the
above mentioned activities (Table 21-1). This drilling total would be expended
through the 2011-2012 drill seasons. The total budget to complete these activities
is estimated at approximately US$3.5M (Table 21-2).
Table 21-1: Recommended Drilling Program for the Pantanillo Norte Property
Holes
Task
Delimiting mineralization in depth
Establishing potential under ignimbrites
Twin holes on old RC holes
In-fill drilling on high-grade areas
Testing for porphyry-style mineralization
Total
7
3
3
6
2
21
Average
Depth
(m)
500
500
300
300
500
Total
Length
(m)
3,500
1,500
900
1,800
1,000
8,700
The budget shown in Table 21-2 should be considered an estimate only, and the
actual costs could vary significantly from this estimate. For this reason, a contingency
of 10% was incorporated into the budget.
Table 21-2: Estimated Budget for the Drill Program and Related Activities for the 20112012 Field Seasons for the Pantanillo Norte Property
Program
Drilling ($200.00/m plus rig mob/demob and supplies)
Laboratory Assays ($40/m)
Geological Supervision and Management (including head office overhead,
travel, accounting, and consultants)
Field Assistants
Field Camp Construction and Supplies (including road maintenance and
equipment, truck rental, kitchen supplies)
Miscellaneous
Sub Total
Contingency (10%)
Total
Cost
(US$)
$1,740,000
$348,000
$500,000
$150,000
$300,000
$100,000
$3,318,000
$314,000
$3,452,000
Hydrogeology, environmental and metallurgical studies are currently being carried out
to support a Scoping Study for the project, which is being conducted by AMEC. This
study will help to improve the understanding of the project’s viability.
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22.0
DATE AND SIGNATURE PAGE
The undersigned prepared this technical report titled “Pantanillo Norte Project, II
Region, Chile, National Instrument 43-101 Technical Report”, with effective date 9 July
2010, and completed on 10 October 2010.
“Signed and sealed”
Armando Simón
AMEC International Ingeniería y Construcción Limitada
P.Geo. (APGO # 1633)
10 October 2010
“Signed”
Paula Larrondo
Member (AusIMM # 302539)
10 October 2010
Joyce Maycock
P. Eng. (APEGBC #13331)
10 October 2010
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CERTIFICATE OF QUALIFIED PERSON
Armando Simón, Ph.D., P.Geo, (AIG, APGO)
Américo Vespucio 100 Sur, 2nd. Floor
Las Condes, Santiago, Chile.
Tel. 56-2-957-7734; Fax 56-2-210-9510
[email protected]
I, Armando Simon, Principal Geologist with AMEC International Ingeniería y Construcción Limitada
(Chile), a division of AMEC Americas Limited, do hereby certify that:
I graduated from the University of Bucharest with a Bachelor of Engineering degree in Geology and
Geophysics in 1974, and a Doctorate of Engineering in 1985.
I am registered as Professional Geoscientist with the Australian Institute of Geoscientists (MAIG # 3003) ,
and with the Association of Professional Geoscientists of Ontario (APGO # 1633).
Since 1974, I have been involved in mineral exploration projects for precious/base metals and industrial
minerals in Argentina, Brazil, Canada, Colombia, Cuba, Chile, Eritrea, Ethiopia, Guyana, Jamaica,
Madagascar, Mexico, Nicaragua, Peru, Pakistan, Portugal, Romania, Russia, and Vietnam.
I visited the Pantanillo Property between 11 and 12 March 2010. I am fully responsible for the preparation
of Sections 1 to 15 and 19 to 23 of the Technical Report entitled “Pantanillo Norte Property, III Region,
Chile, NI 43-101 Technical Report”, with an effective date of 9 July 2010. I have read National Instrument
43-101 and Form 43-101FI, and this report has been prepared in compliance with that instrument and
form.
I have read the definition of “Qualified Person” set out in National Instrument 43-101 (“NI 43-101”) and
certify that, by reason of my education, affiliation with a professional association (as defined in NI 43-101)
and past relevant work experience, I fulfill the requirements to be a “Qualified Person” for the purposes of
this report.
I am independent of Orosur Mining Inc., as independence is described by Section 1.4 of NI 43–101. I
have had no previous involvement with the Pantanillo Property.
As of the date of this certificate, to the best of my knowledge, information and belief, the technical report
contains all scientific and technical information that is required to be disclosed to make the technical
report not misleading.
Armando Simon, P.Geo. (APGO # 1633)
Principal Geologist
10 October 2010
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October, 2010
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Orosur Mining Inc.
Paula Larrondo (MAusIMM)
Tel. 56-2-957-7710; Fax 56-2-210-9510
[email protected]
I, Paula Larrondo, Principal Geostatistician with AMEC International Ingeniería y Construcción Limitada
(Chile), a division of AMEC Americas Limited, do hereby certify that:
I graduated from the University of Chile with Geologist and Master of Science degree in Geology in 2002,
and from the University of Alberta with a Master of Science in Mining Engineering in the field of
Geostatistics in 2004.
I am member of the Australian Institute of Mining and Metallurgy (MAusIMM).
Since 1998, I have been involved in mineral resource estimation of copper and gold projects in South
America.
I have not visited the Pantanillo Property.
I am fully responsible for the preparation of Section 17 of the Technical Report entitled “Pantanillo Norte
Property, III Region, Chile, NI 43-101 Technical Report”, with an effective date of 9 July 2010. I have read
National Instrument 43-101 and Form 43-101FI, and this report has been prepared in compliance with
that instrument and form.
this report.
As of the date of this certificate, to the best of my knowledge, information and belief, the technical report
“Signed”
Paula Larrondo (MAusIMM # 302539)
Principal Geostatistician
10 October 2010
Project No. 3107
October, 2010
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Orosur Mining Inc.
Joyce Maycock, B.Sc. (Eng), A.R.S.M, P. Eng. (APEGBC), Project Manager
Tel. 56-2-957-7700
[email protected]
I, Joyce Maycock, Project Manager with AMEC International Ingeniería y Construcción Limitada, a
division of AMEC Americas Limited, do hereby certify that:
I graduated from the Royal School of Mines, Imperial College, University of London, with a Bachelor of
Science (Engineering) degree in Metallurgy in 1969.
I am registered as a Professional Engineer with the Association of Professional Engineers and
Geoscientists of BC (APEGBC) in British Columbia (License Number 13331).
.
Since 1969 I have continually been involved in mineral processing operations and projects for precious
and base metals in Argentina, Canada, Chile, Peru, and Zambia.
I have not visited the Pantanillos Property. I am fully responsible for the preparation of Section 16 of the
Technical Report titled “Pantanillos Norte Property, III Region, Chile, NI 43-101 Technical Report” with an
effective date of 9 July 2010. I have read National Instrument 43-101 and Form 43-101FI, and this report
has been prepared in compliance with that instrument and form.
this report.
As of the date of this certificate, to the best of my knowledge, information and belief, the Technical Report
Joyce Maycock, P. Eng. (APEGBC # 13331)
Project Manager
10 October 2010
Project No. 3107
October, 2010
Page 22-4
Orosur Mining Inc.
23.0
REFERENCES
Arcuri, T., and Brimhall, G., 2002. Animation Model of West Central South America
from the Early Jurassic to Late Miocene, with Some Oil and Gas Implications. Search
and Discovery Article #10033 (2002), Department of Earth and Planetary Science,
University of California, Berkeley. www.searchanddiscovery.net.
Barra, F.; Fromm, R.; and Valencia, V., 2002. The Andes. In: Dr. George Zandt, GEOS
527 Course on Orogenic Systems (Sec. 001), University of Arizona.
www.geo.arizona.edu/geo5xx/geo527/Andes/home.html.
Callan, N.J., 2005. Pantanillo Au Prospect, Maricunga District, N. Chile: A Preliminary
Geological Review, Evaluation of Previous Work (including drilling) and
Recommendations for Exploration. Internal report prepared for Kinross Minera Chile,
26 November 2006.
Callan, Nick, 2006. Notes to Accompany 1:10,000 Geological Mapping, Pantanillo
Property, Maricunga District. Internal report prepared for Kinross Minera Chile.
Carey, 2010a. Ref: Fortune Valley Resources Chile S.A. (“FV”). Letter submitted to
Armando Simón by María Consuelo Mengual Hernández, from Carey y Cía.
Abogados, dated 30 July 2010.
Carey, 2010b. RE: Legal document regarding Pantanillo Project. E-mail submitted to
Armando Simón by Paloma Infante, from Carey y Cía. Abogados, dated 31 August
2010.
CIA (2010): The World Fact Book: Chile. www.cia.gov/library/publications/the-worldfactbook/geos/ci.html.
CIM, 2000. Exploration Best Practices Guidelines. Adopted by CIM Council, August
20, 2000. Canadian Institute of Mining, Metallurgy and Petroleum.
CIM, 2003. Estimation of Mineral Resources and Mineral Reserves. Best Practices
Guidelines. Adopted by CIM Council, November 23, 2003. Canadian Institute of
Mining, Metallurgy and Petroleum.
CIM, 2005. CIM Definition Standards for Mineral Resources and Mineral Reserves.
Prepared by the CIM Standing Committee on Reserve Definitions. Adopted by CIM
Council, December 11, 2005. The Canadian Institute of Mining, Metallurgy and
Petroleum; 10 p.
Project No. 3107
October, 2010
Page 23-1
Orosur Mining Inc.
CONAF, 1997. Plan de Manejo. Parque Nacional Nevado Tres Cruces. Documento de
Trabajo Nr. 255.
CONAMA, 1994. Ley 19,300 (Bases Generales del Medio Ambiente). Comisión
Nacional del Medio Ambiente, Santiago de Chile, Diario Oficial, 9 de marzo de 1994.
CSA, 2005a. National Instrument 43-101, Standards of Disclosure for Mineral Projects.
Canadian Securities Administrators (CSA); October 7, 2005, 13 p.
CSA, 2005b. Companion Policy 43-101CP to National Instrument 43-101, Standards
of Disclosure for Mineral Projects. Canadian Securities Administrators, 15 p.
CSA, 2005c. National Instrument 43-101, Standards of Disclosure for Mineral Projects.
Canadian Securities Administrators, 14 p.
CSA, 2005d. Form 43-101F1 - Technical Report. Canadian Securities Administrators,
10 p.
Davidson, J., and Mpodozis, C., 1991. Regional geologic setting of epithermal gold
deposits, Chile. Economic Geology, Vol. 86, pp. 1174–1186.
La Cerda, Juan, 2010. Mineral Processing and Metallurgical Testing. Internal
document prepared by Orosur Mining Inc., 10 October 2010.
JGRCh, 1982. Ley 18,097 (Ley Orgánica Constitucional sobre Concesiones Mineras).
Junta de Gobierno de la República de Chile, Santiago de Chile, Diario Oficial, 21 de
enero de 1982.
JGRCh, 1983. Ley 18,248 (Código de Minería). Junta de Gobierno de la República de
Chile, Santiago de Chile, Diario Oficial, 14 de octubre de 1983.
MEFR, 1993. Decreto con Fuerza de Ley Nr. 523 (Texto Refundido, Coordinado y
Sistematizado del Decreto Ley Nr. 600, de 1974, Estatuto de la Inversión Extranjera).
Ministerio de Economía, Fomento y Reconstrucción, Santiago de Chile, Diario Oficial,
16 de diciembre de 1993.
MEFR, 2005. Ley 20,026 (Impuesto Específico a la Actividad Minera). Ministerio de
Economía, Fomento y Reconstrucción, Santiago de Chile, Diario Oficial, 16 de mayo
de 2005.
Mpodozis, C., and Ramos, V.A., 1990. The Andes of Chile and Argentina. In: Ericksen
George, E., Pinochet Maria Teresa, C., and Reinemund John, A., eds., Geology of the
Andes and its relation to hydrocarbon and mineral resources.: Circum-Pacific Council
Project No. 3107
October, 2010
Page 23-2
Orosur Mining Inc.
for Energy and Mineral Resources, Earth Science Series: Houston, TX, United States,
Circum-Pacific Council for Energy and Mineral Resources, p. 59-90.
Muntean, John, and Einaudi, Marco, 2001. Porphyry-Epithermal Transition: Maricunga
Belt, Northern Chile. Economic Geology, Vol. 96, pp. 743–772.
Raab, Alex, 2010. Geology Chapter Pantanillo. Internal document prepared by Orosur
Mining Inc., 20 July 2010.
Siddeley, Gordon, 2009. Technical Report on the Pantanillo Project, Region III,
Atacama, Chile. NI 43-101 report prepared for Fortune Valley Resources Inc., 14
November 2009.
Tassara, Andrés, y Yáñez, Gonzalo, 2003. Relación entre el espesor elástico de la
litósfera y la segmentación tectónica del margen andino (15-47°S). Revista Geológica
de Chile, V. 30, Nr. 2, Diciembre 2003, pp. 159-186.
Vila, T., and Sillitoe, R.H., 1991, Gold-rich Porphyry Systems in the Maricunga Belt,
Northern Chile. Economic Geology, Vol. 86, pp. 1238–1260.
Project No. 3107
October, 2010
Page 23-3

Orosur Mining Inc. Pantanillo Norte Property, III Región, Chile NI 43

Transcription

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