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The beauty of colour
© Swiss Gemmological Institute SSEF
SGG Zentralkurs in Meisterschwanden
Dienstag 21 April 2015
SSEF News
Dr. Michael S. Krzemnicki
Swiss Gemmological Institute SSEF
Photos © M.S. Krzemnicki, SSEF,
except where indicated otherwise
New SSEF office
since January 2015:
Aeschengraben 26
4051 Basel
© Swiss Gemmological Institute SSEF
Jadeite with chromium-rich vein
Avantes
78695_16_jadeite necklace, 536.774ct, it=500, avg=40
3.5
AvaSoft 7.3.1
2.0
Absorbance [A.U]
Absorbance Units
2.5
3.0
1
0
350
400
450
500
600
Wavelength [nm]
700
800
3800
3600
3400
3200
3000
2800
2600
Wavenumber cm-1
C:\DATA\Hong Kong Feb 2015\FTIR\silicate\jadeite\78695\78695_5_jadeite necklace.0
78695_5_jadeite necklace
Instrument type and / or26/02/2015
accessory
Page 1/1
Cr-rich veins are common in jadeite from Myanmar
© T. Cheng!
© Swiss Gemmological Institute SSEF
Brazilian
emerald
in'jadeite0like'
cutting'&'
setting'
Jadeite'necklace'and'ring.'
© Swiss Gemmological Institute SSEF
Emerald
with engraving of
Catherine the Great
Comparing'this'
engraved'portrait'
with'historic'
paintings'shows'a'
very'close'
resemblance,'notably'
with'the'portraits'of'
the'Catherine'the'
Great'(1729'–'1796')'
Empress'of'the'
Russian'Empire'by'
William'Dickinson'
(from'1773)'and'
Virgilius'Erichsen'
(from'1830),'both'
being'part'nowadays'
of'the'State'
Hermitage'Museum'
in'Saint'Petersburg'
(Russia).''
emerald with distinct aquamarine-component
AvaSoft 7.3.1 Avantes 79035_emerald, 14.552ct, it=150, avg=40, halogen
Current Wavelength=602.796 nm
Absorbance [A.U]
1
Fe2+%octahedral%sites%of%the%
beryl,%(8108830%nm)%no%colour%
%
Fe2+%in%the%structural%channels%
(820%nm)%causes%blue%colour%%
%
0
400
500
600
700
800
900
1,000
Wavelength [nm]
© Swiss Gemmological Institute SSEF
Bluish green Cr-bearing beryl
with dominating aquamarine-component
The%bands%370%and%
420%nm%due%to%
octahedral%Fe3+%and%
induce%a%yellowish%
(greenish)%colour%%
54.84%ct%
300
400
500
© Swiss Gemmological Institute SSEF
Fe2+%in%the%
structural%
channels%%
(820%nm)%
causes%the%
blue%colour%%
%
600
700
800
900
1000
Bluish green emerald
with no aquamarine-component
AvaSoft 7.3.1 Avantes 78887_emerald, 9.456ct, it=100, avg=40
Current Wavelength=602.796 nm
Bluish%green%colour%due%to%
absence%of%Fe3+%in%octahedral%
sites%%resulFng%in%transmission8
window%in%the%blue%(and%LWUV)%
9.46%ct%
Absorbance [A.U]
1
Very%low%Fe2+%
in%octahedral%
sites%and%in%
the%structural%
channels:%
No%colour%
contribuFon%
0
300
350
400
450
500
550
600
650
Wavelength [nm]
© Swiss Gemmological Institute SSEF
Hydrothermal synthetic emerald of 67 ct
© Swiss Gemmological Institute SSEF
700
750
800
850
900
Emerald imitation: Foiled back topaz
La Belle of Asia…
Historical%sapphire%from%Ceylon%of%392.52%ct%
Sold%at%aucFon%in%November%2014,%World%record%$17,295,796%
SSEF%report%no.%72359%
© Swiss Gemmological Institute SSEF
Exceptional Kashmir sapphires
Highly'matching'
in'colour'and'
outstanding'
clarity'
© Swiss Gemmological Institute SSEF
BYG Sapphires from basaltic deposits
Photo: Sutas Singbamroon!
Sapphires from Nigeria (Basaltic source)
5!
!!
!
NEWS FROM RESEARCH
!
The report indicates the status of a research project that is still ongoing within GIA Laboratory Bangkok.
Comments on this and other reports and their direction are warmly welcomed as are offers of collaboration. Please
contact: [email protected] stating the name of the project and name(s) of the author(s).
Blue%sapphires(,
from%the$Mambilla'Plateau,!,
Taraba%State,"Nigeria!
!
A!preliminary!examination!
Vincent!Pardieu,!Supharart!Sangsawong,!Jonathan!Muyal,!Nicholas!Sturman.!
GIA!Laboratory,!Bangkok!
August!16 th ,!2014!
Photos & maps: V. Pardieu, 2014!
!
!
Figure'4:'Local'map'(modified'from'Google'Earth)'of'the'Mambilla'Plateau'area'with'the'approximate'location'of'the'new'
deposit'shown,'near'Guroji'according'to'the'information'provided'by'local'miners.'The'old'diggings'producing'small'dark'blue'
stones'seem'to'be'located'near'Gembu'close'to'the'border'with'Cameroon.'The'exact'location'of'these'deposits'still'needs'to'
be' confirmed.' Note:' The' photos' of' the' single' stones' illustrated' in' this' map' are' of' one' stone' weighing' over' 100' carats,'
reportedly' from' the' new' deposit,' and' another' of' about' 8' carats' courtesy' Brume' Jeroh.' Map:' Vincent' Pardieu' /' GIA'
Laboratory'Bangkok.'
!
Sadly!the!GIA!field!expedition!to!Nigeria!planned!for!the!end!of!April!2014!had!to!be!postponed!
and!with!the!advent!of!the!rainy!season!in!Nigeria,!it!was!difficult!to!plan!another!expedition!
before!the!completion!of!this!report.!Thus!this!study!will!only!be!a!“preliminary!report”!as!it!is!
based!on!F!type!samples!(per!GIA!Field!Gemology!department!terminology,!see!Annex!A)!which!
means!that!these!samples!were!collected!from!trustworthy!West!African!sources!in!Bangkok.!At!
the!beginning!of!June!2014,!as!the!field!expedition!was!postponed,!we!decided!to!acquire!some!
interesting!parcels!of!fine!quality!rough!sapphires,!reportedly!from!the!Mambilla!area,!in!order!
!
Figure'1:'Parcel'of'30'rough'blue'sapphires'reportedly'from'the'Mambilla'area,'Nigeria'seen'in'Bangkok'on'June'05th'2014.'
The'weight'of'the'stones'is'between'1'and'5'carats.'Photo:'Vincent'Pardieu'©'GIA.'
to! start! a! preliminary! study! on! the! new! material.! Our! plans! are! to! confirm! these! results!
in!
future! after! visiting! the! new! sapphire! mining! area! and! completing! a! study! of! the! samples!
©!GIA!
http://www.gia.edu!
August!16 ,!2014!
collected!on!site!at!the!time.!!
!
th
Figure'4:'Local'map'(modified'from'Google'Earth)'of'the'Mambilla'Plateau'area'with'the
deposit'shown,'near'Guroji'according'to'the'information'provided'by'local'miners.'The'old
!
!
!
!
stones'seem'to'be'located'near'Gembu'close'to'the'border'with'Cameroon.'The'exact'loca
be' confirmed.' Note:' The' photos' of' the' single' stones' illustrated' in' this' map' are' of' one
Typical'features'of'basaltic'sapphires:'
reportedly'
from' the' new' deposit,' and' another' of' about' 8' carats' courtesy' Brume' Je
'
Laboratory'Bangkok.'
©!GIA
0 
0 
0 
0 
th
http://www.gia.edu
August!15 ,!2014
Often'greenish'blue'colour'
Quite'often'distinct'milkyness'
Fe0rich:'Characteristic'absorption'spectrum'
Distinct'OH0'(hydroxyl)'in'IR'spectrum'
!
Sadly!the!GIA!field!expedition!to!Nigeria!planned!for!the!end!of!April!
5.58'ct'
and!with!the!advent!of!the!rainy!season!in!Nigeria,!it!was!difficult!t
before!the!completion!of!this!report.!Thus!this!study!will!only!be!a!“
FTIR&
UV#Vis&
based!on!F!type!samples!(per!GIA!Field!Gemology!department!termin
3309%cm
means!that!these!samples!were!collected!from!trustworthy!West!Afri
the!beginning!of!June!2014,!as!the!field!expedition!was!postponed,!w
interesting!parcels!of!fine!quality!rough!sapphires,!reportedly!from!t
to! start! a! preliminary! study! on! the! new! material.! Our! plans! are! t
future! after! visiting! the! new! sapphire! mining! area! and! completin
collected!on!site!at!the!time.!!
!
Absorbance Units
0.90
0.95
81%
1
0.85
Absorbance [A.U]
1.00
AvaSoft 7.3.1 Avantes 76575_research_sapphire, 5.577ct, int=40, avg=40
Current Wavelength=454.455 nm
4000
300
350
400
450
500
550
600
Wavelength [nm]
650
700
750
3500
3000
Wavenumber cm-1
2500
2000
Ruby
Heat'treatment'rarely'applied''
on'spinels'so'far:'
0  Only'limited'enhancement'
0  Colour'change'only'slight'
0  Fine'milkyness'is'said'to'be'reduced.'
Heated ruby from Mozambique
Neo0healing']issure'charactersitic'for'heat'treatment''
(and'FTIR'peaks'at'3309'cm01'with'small'side'bands)'
© Swiss Gemmological Institute SSEF
Exceptional unheated ruby from Mozambique 23 ct
AvaSoft 7.3.1 Avantes 78805_ruby, 23.018ct, it=200, avg=40
Current Wavelength=492.381 nm
Absorbance [A.U]
1
0
350
400
450
500
550
600
650
700
750
800
Wavelength [nm]
No'indications'of'heating,'Ceylon'(Sri'Lanka)'
© Swiss Gemmological Institute SSEF
New
world record
Unheated
ruby 23for
ct ruby ?
The%Sunrise%ruby,%a%25.59%ct%Burmese%ruby%of%"pigeon's%blood"%hue,%
will%be%offered%at%aucFon%by%Sotheby's%Geneva%on%12%May%2015%
with%an%esFmated%value%of%$12818million.%
Latest&news&13th&May&2015:&&
Sold&for&30.3&million&US$&
27 ct Burmese ruby in a historic setting
Rather'highly'fractured'material.'
©©Swiss
SwissGemmological
GemmologicalInstitute
InstituteSSEF
SSEF
Padparadscha from Ceylon, 46 ct
AvaSoft 7.3.1 Avantes 78933_orange sapphire, 46.919ct, it=300, avg=40
Current Wavelength=602.796 nm
Absorbance [A.U]
1
Colour%is%a%combinaFon%of%Cr3+,%Fe3+%and%yellow%colour%centre%
0
300
350
400
450
500
550
600
Wavelength [nm]
650
700
750
800
850
© Swiss Gemmological Institute SSEF
Yellow sapphire with unstable colour!
18.09'ct'
Heated spinel from Tanzania
Heat'treatment'rarely'applied'on'spinels'so'far:'
0  Only'limited'enhancement'
0  Colour'change'only'slight'
0  Fine'milkyness'is'said'to'be'reduced.'
Heated spinel from Tanzania
AvaSoft 7.3.1 Avantes 76610 red spinel and reference of unheated red spinel
Current Wavelength=683.179 nm
01: amp=9061.3
it=300.00 av=30 s=0 71196_0001.roh: 1305157U1- 71196, red spinel, 10.780ct, PL, IT=300ms, Avg=30
60,000
50,000
Counts
40,000
unheated%
30,000
20,000
10,000
heated%
0
640
660
680
700
720
740
760
Wavelength [nm]
Diamond wi(n)dow
Diamond Crrrrracks...
Ca.'10'ct'
Cleavage%cracks%due%to%mechanical%shock%at%table%edge,%but%assisted%by%„fixed“%se`ng.%
© Swiss Gemmological Institute SSEF
Surface alterations of Conch pearls:
Conch pearl with organic surface layer
Originally%interpreted%as%a%varnish%=%surface%
treatment%(SSEF%press%release%September%2013),%this%
is%in%fact%a%natural%organic%cover%ocen%seen%parFally%
on%conch%pearls.%
Conch pearls
with damaged
(corroded)
surface
Surface%alteraFon%(corrosion)%due%to%
exposure%to%acidic%soluFons%
Stability testing with cosmetics
EN%43882%(NIHS%968508paragraph%6.8/6.9)%
© Swiss Gemmological Institute SSEF
Stability testing with sweat (synthetic)
ISO%316082%:%2003%and%NIHS%96850%:%2013%
© Swiss Gemmological Institute SSEF
The Cirebon ship wreck (ca. 10th century)
hfp://cirebon.musee8mariemont.be/the8wreck%
Pearls from the Cirebon wreck (ca. 10th century)
Chinese%coins%and%ceramics%firmly%place%
the%wreck%in%the%10th%Century%AD.%
Radiocarbon age dating of these pearls
The%14C%daFng%perfectly%fits%
with%the%assumed%date%of%
this%ship%wreck%based%on%
pofery%and%coins.%
%
Project%with%ETH8Zurich%
Christie‘s
New York
14th April 2015
US$ 5.1 million
289%natural%pearls%of%
partly%remarkable%size%
(maximum%diameter%
up%to%12.65%mm%
approximately),%
strung%on%four%
smoothly%and%
regularly%graduated%
strands.%%
%
18.09'ct'
Thank you for
your attention
For%more%informaFon,%check%www.ssef.ch%