FUSIONS – HOW TO IMPROVE THROUGHPUT AND
Transcription
FUSIONS – HOW TO IMPROVE THROUGHPUT AND
FUSIONS – HOW TO IMPROVE THROUGHPUT AND CONCENTRATION RANGE OF ANALYSIS BY ELIMINATING THE LOSS ON IGNITION PROCESS STEP, USING DIFFERENT DILUTION RATIOS AND MAINTAINING ACCURACY AND PRECISION OF RESULTS Laura Oelofse (Rigaku Americas) and Yoshijuro Yamada (Rigaku Corporation ) Abstract The use of fusions for XRF in industrial process monitoring is common practice and there are several time consuming steps to complete in order to render a sample fusion ready. This paper details a method that would eliminate the need to carry out the Loss on Ignition, Gain on Ignition step thus eliminating 2 hrs from the preparation time and it also details the ability to use different dilution ratios of sample and flux for materials on the same calibration curve in order to increase the scope of materials that can be included in a universal calibration curve using both naturally sourced certified reference materials and synthetic pure chemicals as calibration standards Analysis Schemes in Various Industry Sectors Composition varies in narrow range Widely varying composition Incoming Raw Materials Product XRFs Role in High Throughput Solutions Results Analysis Sample Introduction Sample Preparation Sample Loading Fusions – Flux + Sample All compounds changed to oxide form Eliminate Particle Size Effect Eliminate Mineralogical Effect Some Typical Fused Glass Beads 6 Why Preparation of Fused Glass Beads • Particle size and mineralogical effects are removed or diminished by fusion of the sample with a suitable flux to form a glass bead. • Synthetic calibration standards can be made by mixing pure oxides at concentration levels to suit the analytical range. • Depending on sample type, fusion can even be quicker than pressed powder procedure. • Generally accuracies and reproducibility are superior with fusion procedure. • Only drawback is possible dilution of trace elements and therefore inferior LLD. Low dilution fusions are possible. 7 Preparation of Fused Glass Beads Melting method Heat for Melting Weigh out and mix Flux + Specimen Cast & Cool 1000° -1100° C To standard holder Glass disk specimen Platinum crucible Remove bubbles 9499D00500 3 - 7 mins 8 - 15 mins 5 mins 8 Preparation of Fused Glass Beads • Preparation of powder as fused glass bead involves weighing out sample and flux, placing in Gold/Platinum crucible, heating to 1000 – 1200 degrees and casting as a flat glass bead by pouring melt into a heated Gold/Platinum mould and cooling under controlled conditions. • Newer alternative is moldable where melt remains in crucible and bead is formed in situ. • DEPENDING ON NATURE OF SAMPLE – LOSS ON IGNITION MAY BE NECESSARY. ( CEMENTS, LIMESTONE, DOLEMITE) 9 In reality there are three types of samples Type 1 – Sample is stable, no loss or gain during fusion process Sample Flux F S Type 2 : Sample loses CO2 or Intrinsic Waters during fusion, known as Loss on Ignition LOI Sample Flux F S Type 3: Sample loses CO2 or Intrinsic Waters during fusion, known as LOI and changes oxidation state and pick up oxygen, gaining on ignition, known as GOI LOI Sample S Flux Replaced with flux B GOI Analytical Error Factors in Fusion Method The errors can be removed by Rigaku Bead Correction method Powder Sample Heterogeneity Effect Grain-size Effect Mineralogical Effect Fusion Bead Weighing Error Loss on Ignition Gain on Ignition Evaporation of Flux Error factors for Bead Error Factors in Fusion Method Fusing Weighing Weighing error(1) GOI (3) O2 Sample FeO Flux(Li2B4O7 etc) Bead (4) Flux LOI evaporation (2) CO2 H O 2 Fe2O3 Pt crucible 1000-1200˚ C The four error factors can be corrected. Strategy for the Corrections of LOI, GOI and Dilution Ratio Model 1 : Use of Ratio of flux to sample weight ( F/S) LOI Sample Flux F S Definition of LOI : Imaginary component with no x-ray absorption Correction LOI(GOI) : Concentration is manually input or calculated as balance Dilution ratio : Corrected by manual input of F/S Model 2 : Use of Ratio of bead to sample weight( B/S) LOI Sample S Flux Replaced with flux B Definition of LOI : Imaginary component of flux Correction : LOI(GOI) : Concentration is manually input or calculated as balance Dilution ratio : Corrected by manual input of B/S (Note) Flux evaporation can be corrected Analysis in Fused Beads Use of fusion bead correction Software generates theoretical alphas for LOI/GOI and dilution ratio Calibration equation Wi (aI 2 bI C)(1 K αjWj αLOIWLOI αFRF) The alphas correct for LOI/GOI Dilution ratio and Flux evaporation during fusing The alphas are generated by using a fundamental parameter software and it generates variety of models. Dilution ratio models : Flux weight to sample weight(F/S) or bead weight to sample weight(B/S) LOI/GOI : Loss eliminated or manual input Rigaku Fusion Bead Correction Software • Allows for varying flux : sample ratios and the use of catch weights • Allows calculation of the Loss on Ignition /Gain on Ignition and flux loss component by balance or ratio input BCS376 LOI 0 LOI 10 SiO2 67.1 67.42 60.68 TiO2 0.02 0.02 0.02 Al2O3 17.7 17.79 16.01 Fe2O3 0.10 0.10 0.09 CaO 0.54 0.54 0.49 MgO 0.03 0.03 0.03 Na2O 2.83 2.84 2.56 K2O 11.2 11.25 10.13 LOI 0.35 0.00 10.00 Total 99.87 99.99 100.01 Sample (g) 0.3000 0.2700 Li2B4O7 ( g) 3.0000 3.0000 60 50 40 LOI XRF Oxides 30 LOI CHEM Lineær (LOI CHEM) 20 10 0 0 20 LOI CHEM -10 40 60 Fusion Bead Correction for LOI in Various Kinds of Materials BCS393 (Limestone) Chem. XRF Diff. NBS69b Chem (Bauxite) XRF Diff. NBS697 Chem (Bauxite) XRF Diff. NBS97a Chem (Clay) XRF Diff. JDo 1 Chem (Dolomite) XRF Diff. BCS375 Chem (Feldspar) XRF Diff. R801 Chem (Pyrophyllite) XRF Diff. BCS314 Chem (Silica brick) XRF Diff. SiO2 TiO2 Al2O3 Fe2O3 MnO MgO 0.70 0.01 0.12 0.05 0.01 0.15 0.77 0.02 0.16 0.03 0.00 0.13 -0.07 0.01 0.04 -0.02 -0.01 -0.02 13.57 1.92 49.29 7.21 0.11 0.09 13.68 1.92 49.28 7.25 0.11 0.14 0.11 0.00 -0.01 0.04 0.00 0.05 6.84 2.53 45.99 20.09 0.41 0.18 6.88 2.51 45.98 20.15 0.42 0.25 0.04 -0.02 -0.01 0.06 0.01 0.07 44.00 1.91 39.06 0.45 0.00 0.15 43.89 1.93 38.72 0.45 0.00 0.09 -0.11 0.02 -0.34 0.00 0.00 -0.06 0.21 0.00 0.01 0.02 0.01 18.58 0.28 0.01 0.06 0.01 0.00 18.87 0.07 0.01 0.05 -0.01 -0.01 0.29 67.15 0.38 19.82 0.12 0.00 0.05 67.80 0.38 20.05 0.10 0.00 0.07 0.65 0.00 0.23 0.02 0.00 0.02 78.64 0.10 16.76 0.17 0.00 0.04 78.62 0.10 16.71 0.17 0.00 0.08 -0.02 0.00 -0.05 0.00 0.00 0.04 96.40 0.19 0.77 0.53 0.01 1.81 96.47 0.20 0.79 0.49 0.00 1.86 0.07 0.01 0.02 -0.04 -0.01 0.05 CaO Na2O 55.46 0.03 55.78 0.00 0.32 -0.03 0.13 0.03 0.17 0.00 0.04 -0.03 0.71 0.04 0.78 0.00 0.07 -0.04 0.11 0.04 0.13 0.01 0.02 -0.03 33.94 0.01 33.95 0.00 0.01 -0.01 0.89 10.41 0.87 9.95 -0.02 -0.46 0.04 0.22 0.08 0.16 0.04 -0.06 1.81 0.05 1.86 0.01 0.05 -0.04 K2O 0.02 0.01 -0.01 0.07 0.07 0.00 0.06 0.06 0.00 0.50 0.58 0.08 0.00 0.00 0.00 0.79 0.74 -0.05 0.18 0.19 0.01 0.09 0.08 -0.01 P2O5 0.01 0.00 -0.01 0.12 0.11 -0.01 0.97 0.97 0.00 0.36 0.37 0.01 0.04 0.03 -0.01 0.00 0.01 0.01 0.00 0.02 0.02 0.00 0.01 0.01 LOI 43.44 43.10 -0.34 27.46 26.99 -0.47 22.18 22.00 -0.18 13.42 13.83 0.41 47.18 46.79 -0.39 0.39 0.03 -0.36 3.86 3.88 0.02 0.10 0.01 -0.09 Results are obtained by using theoretical alphas and LOIs are obtained as balance. The accuracy of the calculated LOI across the range of 0 % - 50% is 0.5% Quantification and Correction of Gain on Ignition Synthetic mixtures of SiO2 and FeO were blended to yield 30%, 50% and 70% FeO During fusion the FeO is oxidized to Fe2O3 and there is a weight gain of (Fe2O3 – 2FeO)/ 2FeO The mass absorption coefficient of GOI is set to zero and the value is considered as a negative LOI in the FP calculation. The WFe2O3 = WFeO + W GOI SiO2 FeO calc. Recalc. FP value 70.00 30.00 calc. Recalc. FP value 50.00 calc. Recalc. FP value 30.00 Fe2O3 32.27 32.48 50.00 52.64 52.84 70.00 72.17 72.15 Determination of GOI from Standard Iron Ore Fe2O3 Diff Chem XRF JSS 803-2 89.57 89.71 0.14 JSS830-3 84.18 84.16 -0.02 Euro 680-1 86.33 86.31 -0.02 ASCRM 004 89.43 89.51 0.08 • Method applied to iron ore with high Fe content and shown to be suitable Dilution Ratio Correction STD S:F 1:5 JB-2 UNK S:F 1:10 JG-1 Lit. FP Lit. SiO2 52.83 73.06 72.75 TiO2 1.18 0.28 0.26 Al2O3 14.57 14.02 14.29 Fe2O3 14.24 2.13 2.21 MnO 0.20 0.06 0.06 MgO 4.63 0.71 0.75 CaO 9.82 2.18 2.19 Na2O 2.02 3.38 3.41 K2O 0.43 4.10 3.97 P2O5 0.10 0.09 0.10 Application of LOI, GOI and dilution ratio correction to Empirical Calibration Methods • Matrix correction coefficients were theoretically calculated for LOI, GOI and dilution ratio correction components • The matrix correction expression including the dilution ratio correction is shown on the next slide • Using the Theoretical Alpha Correction model where the base component is considered to be the LOI/GOI/D.C then these are eliminated in the De Jongh calculation and are calculated as a balance component. • The accuracy for Fe2O3 in a regression of geological standards for an uncorrected calibration was 0.161%, for a calibration with conventional matrix corrections 0.066% and for theoretical matrix correction coefficients with LOI and GOI correction an improved accuracy of 0.056% Rigaku Theoretical Alphas for Fusion Bead Correction equation of T.Fe Wi = (aiIi2+biIi +c)*(1+SajWj + aFRF - KF) Factor Coefficient K 0.910900 a(T.Fe) 0.002392 a( SiO2) 0.001413 a(Mn) 0.002923 a(CaO) 0.006793 a(MgO) 0.000967 a(Al2O3) 0.001128 a(TiO2) 0.006700 a(P) 0.003929 a(S) 0.004874 a(K) 0.008125 a(FLUX) 0.089130 1. The correction coefficients a j for inter-elements and flux are calculated theoretically by Rigaku/FP software. These alphas depend on the optics of spectrometer. 2. K corresponds to the standard dilution ratio. 3. When the actual dilution ratio “ RF” ( Bead weight/ sample weight ) is input for the each sample manually, all error factors are automatically corrected. ( LOI, GOI and Dilution Correction) 4. Calibration constants (a,b,c) are calculated using the nonlinear regression equation , after standard samples are measured. Dilution Ratio Correction Calibration equation with dilution ratio correction Wi b I i c 1 a j Wj a F R F K F j L K F aFR F General calibration equation Wi b I i c 1 a j Wj a F R F R F R F R F aFRF + KF is the correction term for the difference between the actual and standard dilution ratio. RF : Difference between the actual and standard ratio RF : Actual dilution ratio Matrix Correction Model Correction model Lachance-Traill Uncorrected component Analyte Notes Correction by all the components except the analyte. The calibration curve is linear. de Jongh Base component Correction by all the elements except the base component. The calibration curve is linear. JIS Base component and analyte Correction by all the elements except the base component and the analyte. The calibration curve is linear or quadratic. When a significant amount of LOI (GOI) is contained, it is advisable to use de Jongh or JIS model. SiO2 Calibration Curve Analysis sample: rock fusion disk (dilution ratio 5:1) de Jongh model X-ray intensity (a. u.) X-ray intensity (a. u.) JIS model Accuracy: 0.18 mass% Standard value (mass%) Accuracy: 0.17 mass% Standard value (mass%) considering self-absorption by the analyte CaO Calibration Curve Analysis sample: rock fusion disk (dilution ratio 5:1) de Jongh model X-ray intensity (a. u.) X-ray intensity (a. u.) JIS model Accuracy: 0.17 mass% Standard value (mass%) Accuracy: 0.14 mass% Standard value (mass%) considering self-absorption by the analyte Comparison of Matrix Correction Coefficients between Several Materials by the Fusion Method — Analysis of Refractories — Calibration Range of the Major Components and Dilution Ratio for Each Material Material Major component (mass%) SiO2 Al2O3 Fe2O3 MgO 6–49 Silica 84–97 –10 10 –44 47–94 10 81–99 Chrome-magnesia –27 Zircon-zirconia –45 Alumina-zirconia-silica –42 Alumina-magnesia The whole range –1 (Flux/Sample) 37–86 Magnesia –1 ZrO2 Clay High alumina –5 Cr2O3 Dilution ratio 10 2–53 10–82 10–93 –97 10–52 –94 22.16 48–92 10 12–48 10 3–79 –27 –99 • Wide calibration range • Different dilution ratio 10 10 –53 –92 10–22.16 • Flux: Li2B4O7 • LiNO3 was used just for Chrome-magnesia. Comparison of Matrix Correction Coefficients for Each Material (1) Clay Alumina-Zircon-Silica SiO2 Analyte Correcting comp. Al2O3 Fe2O3 TiO2 MnO CaO MgO Na2O K2O P2O5 Cr2O3 ZrO2 High alumina 1.38E-03 1.02E-03 2.44E-04 8.65E-04 6.91E-05 1.33E-03 1.04E-03 -5.41E-05 -1.88E-05 6.06E-04 8.76E-04 Si-Ka 1.38E-03 1.01E-03 2.41E-04 8.62E-04 6.60E-05 1.33E-03 1.04E-03 -5.75E-05 1.37E-03 1.02E-03 2.43E-04 6.81E-05 1.33E-03 1.04E-03 -5.49E-05 6.07E-04 8.68E-04 Correction model: Lachance-Traill Correction coefficients are almost identical for each material. SiO2 Calibration Curve Magnified Magnesi a X-ray intensity (a. u.) X-ray intensity (a. u.) Accuracy: 0.25 mass% Silica Clay AZS AZS ◆ 10 : 1 ◆ 22.16 : 1 Chrome-magnesia (Chrome-magnesia) Standard value (mass%) Standard value (mass%) AZS: Alumina-zirconia-silica Comparison of Matrix Correction Coefficients for Each Material (2) Clay Alumina-Zircon-Silica Fe2O3 Analyte Correcting comp. SiO2 Al2O3 TiO2 MnO CaO MgO Na2O K2O P2O5 Cr2O3 ZrO2 High alumina -1.88E-03 -2.19E-03 3.93E-03 -1.94E-04 4.03E-03 -2.37E-03 -2.62E-03 3.94E-03 -1.65E-03 7.27E-03 1.09E-03 Fe-Ka -1.87E-03 -2.18E-03 3.95E-03 -1.93E-04 4.04E-03 -2.36E-03 -2.61E-03 3.96E-03 -2.06E-03 -2.37E-03 3.64E-03 3.72E-03 -2.54E-03 -2.79E-03 3.64E-03 6.91E-03 1.30E-03 Correction model: Lachance-Traill Correction coefficients are almost identical for each material. Fe2O3 Calibration Curve Magnified Chrome-magnesia Accuracy: 0.029 mass% ◆ 10 : 1 X-ray intensity (a. u.) X-ray intensity (a. u.) Magnesi a Chrome-magnesia ◆ 22.16 : 1 Zircon-zirconia (Chrome-magnesia) Standard value (mass%) Standard value (mass%) AZS: Alumina-zirconia-silica Dilution Ratio Correction + Matrix Correction Rock sample Analyte GSJ: : dilution ratio 10:1 and 5:1 : SiO2 Analysis sample CCRMP: SY-2, SY-3 JA1, JA2, JA3, JB2, JB3, JG1a, JG2, JG3, JGb1, JR1, JR2, JLs1, JCp1 Dilution Ratio Correction Rock sample Analyte : dilution ratio 10:1 and 5:1 : SiO2 No correction X-ray intensity (a. u.) X-ray intensity (a. u.) Accuracy: 11 mass% ●:5:1 ●:10:1 Standard value (mass%) Dilution ratio correction Accuracy: 3.6 mass% ●:5:1 ●:10:1 Standard value (mass%) The dilution ratio correction improves the accuracy; however, the fitting is still not excellent due to matrix effect. Dilution Ratio Correction + Matrix Correction Dilution ratio correction Accuracy: 3.6 mass% ● 5:1 ● 10:1 Standard value (mass%) : dilution ratio 10:1 and 5:1 : SiO2 X-ray intensity (a. u.) X-ray intensity (a. u.) Rock sample Analyte Dilution ratio cor. + Matrix cor. Accuracy: 0.33 mass% ● 5:1 ● 10:1 Standard value (mass%) The combination of the dilution ratio and matrix corrections enables an excellent fitting. LOI Correction (1) • Test sample: rock sample with 50 mass% LOI (the bead was made with the dilution ratio 10:1, and then treated as the dilution ratio 5:1, which results in the sample with 50 mass% LOI.) • Analyte: SiO2 LOI Correction and Matrix Correction Coefficients Correction model: de Jongh Element line: Si-Ka Without LOI cor. With LOI cor. Base component SiO2 LOI Na2O MgO Al2O3 SiO2 P2O5 K2O CaO TiO2 MnO Fe2O3 -4.79E-04 -6.32E-05 5.15E-03 5.81E-03 5.91E-03 2.78E-03 2.74E-03 2.67E-03 2.94E-03 3.35E-03 4.76E-03 5.11E-03 -1.97E-03 -1.99E-03 -2.03E-03 -1.87E-03 -1.61E-03 -7.21E-04 5.03E-04 Matrix Correction (without LOI Correction) Analyte : SiO2 Accuracy: 2.5 mass% ● w/o LOI ● with LOI Standard value (mass%) X-ray intensity (a. u.) X-ray intensity (a. u.) No correction Matrix correction Accuracy: 3.5 mass% ● w/o LOI ● with LOI Standard value (mass%) LOI Correction and Matrix Correction Matrix correction Accuracy: 3.5 mass% ● w/o LOI ● with LOI Standard value (mass%) : SiO2 X-ray intensity (a. u.) X-ray intensity (a. u.) Analyte LOI correction + Matrix cor. Accuracy: 0.26 mass% ● w/o LOI ● with LOI Standard value (mass%) Wide Analysis Range in XRF Analysis of Diverse Natural Minerals by the Fusion Method (Synthetic Fusion Bead Added) Purpose of This Test Analysis • To obtain a good fitting for calibration curves with wide concentration range of diverse natural minerals by the fusion method • To obtain a good fitting for calibration curves with synthetic standard fused beads Reference Materials for Calibration (1) Sample Material Dil. ratio Sample Material Dil. ratio BAS203a Talc 10 NBS688 Basalt rock 10 BCS313-1 High purity silica 10 SRM 1c Limestone 10 BCS314 Silica brick 10 SRM 69b-1 Bauxite 10 BCS315 Fire brick 10 SRM 696 Bauxite Surinam 10 BCS319 Magnesite 10 SRM 697 Bauxite Dominican 10 BCS368 Dolomite 10 SRM 698 Bauxite Jamaican 10 BCS369 Magnesite-Chrome 22.167 SRM 70a Potash feldspar 10 BCS370 Magnesite-chrome 22.167 SRM 99a Soda feldspar 10 BCS375 Soda feldspar 10 R-603 Clay 10 BCS376_1 Potash feldspar 10 R-701 Feldspar 10 BCS358 Zirconia 10 R-801 Pyrophyllite 10 BCS388 Zircon 10 JSS009-2 Pure iron oxide 10 BCS389 High purity magnesium 10 JRRM511 Chrome-magnesia 22.167 BCS393 Limestone 10 JRRM602 Zirconia 10 BCS394 Calcined bauxite 10 JRRM701 AZS 10 BCS395 Bauxite 10 RM-611 Portland cement 10 NBS98a Plastic clay 10 RM-612 Portland cement 10 NBS120c Florida phosphate rock 10 RM-613 Portland cement 10 Reference Materials for Calibration (2) Sample Material Dil. ratio Notes ECISS782-1 Dolomite 10 ECISS776-1 Fire brick 10 BCS348 Ball clay 10 NIST 81a Glass sand 10 NIST 278_1 Obsidian rock 10 NIST 1413 Glass sand 10 NBS694 Phosphate rock 10 BAS 683-1-(1) Iron ore sinter 10.13 BAS 683-1-(2) Iron ore sinter 10.13 BCS315_Co1 Fire brick with Co AA standard sol. 10 For analysis of Co from the WC container BCS315_W1 Fire brick with W AA standard sol. 10 For analysis of W from the WC container NIST278_1_Co05 Obsidian rock with Co AA standard sol. 10 For analysis of Co from the WC container NIST278_1_W05 Obsidian rock with W AA standard sol. 10 For analysis of W from the WC container TiO2_10 TiO2 reagent 10 To extend TiO2 calibration range P2O5_25 LiPO3 reagent 10 To extend P2O5 calibration range K2O_50 K2CO3 reagent 10 To extend K2O calibration range CaO_100 CaCO3 reagent 10 To extend CaO calibration range Na2O_25 Na2CO3 reagent 10 To extend Na2O calibration range Calibration Range Unit: mass% Analyte Calibration range Analyte Calibration range Na2O 0 – 25 Fe2O3 0 – 99.84 MgO 0 – 96.7 Cr2O3 0 – 52.51 Al2O3 0 – 88.8 ZrO2 0 – 92.7 SiO2 0 – 99.78 HfO2 0 – 1.63 P2O5 0 – 33.34 SO3 0 – 6.07 K2O 0 – 50 SrO 0 – 0.28 CaO 0 – 100 Co2O3 0 – 1.407 TiO2 0 – 10 WO3 0 – 1.261 MnO 0 – 0.596 Li2B4O7 10 – 22.167 Dilution ratio (flux/sample) Na2O calibration MgO calibration Na2CO3 Synthetic bead Accuracy: 0.048 mass% Standard value (mass%) X-ray intensity (a. u.) X-ray intensity (a. u.) Accuracy: 0.40 mass% BCS370 Mg-Cr BCS369 Mg-Cr Standard value (mass%) SiO2 calibration X-ray intensity (a. u.) X-ray intensity (a. u.) Al2O3 calibration Accuracy: 0.23 mass% Standard value (mass%) Accuracy: 0.35 mass% Standard value (mass%) P2O5 calibration SO3 calibration Phosphat e rock Accuracy: 0.017 mass% Standard value (mass%) X-ray intensity (a. u.) X-ray intensity (a. u.) LiPO3 Synthetic bead Portland cement Accuracy: 0.056 mass% Standard value (mass%) K2O calibration CaO calibration CaCO3 Synthetic bead X-ray intensity (a. u.) X-ray intensity (a. u.) K2CO3 Synthetic bead Accuracy: 0.021 mass% Standard value (mass%) Accuracy: 0.27 mass% Standard value (mass%) TiO2 calibration Fe2O3 calibration Fe2O3 Synthetic bead X-ray intensity (a. u.) X-ray intensity (a. u.) TiO2 Synthetic bead Accuracy: 0.027 mass% Standard value (mass%) Iron ore Accuracy: 0.067 mass% Standard value (mass%) Summary • By applying the dilution ratio correction, LOI correction and matrix correction (theoretical alphas), it is possible to obtain a good fitting for calibration curves with wide concentration range for diverse natural rocks and minerals by the fusion method. • With a few calibration standards, it is necessary to use the de Jongh or Lachance-Traill models, where calibration curves are linear in theory. In this test, de Jongh model was used because some samples contain significant LOI content. • With a large number of calibration standards, it is possible to use the JIS model, where calibration curves can be quadratic. • With synthetic fused beads to extend the calibration range, it is possible to obtain a good fitting for calibration curves. Conclusion • The fusion bead method is useful sample preparation for eliminating hetrogeneity effects, particle size effects, however chemical reactions can cause the sample weight to decrease or/and increase during fusion because of volatilization of H2O, CO2 and oxidation. • It is possible to correct error factors in fusion for either the FP method or the Empirical Calibration method. • It is possible to skip the lengthy independent LOI step in preparing the samples for fusion, by incorporating the step into the fusion process and correcting for the associated losses and/or gains via the correction methods just detailed • It is possible to weigh catch weights and have them recorded in the dilution correction. • The time savings realized by eliminating the LOI step and supporting varying dilution ratios improves throughput and cuts the analysis cost per sample • Thank you for your attention