RE-EVALUATION OF JAPANESE GEOLOGICAL REFERENCE MATERIALS (JSD/JDO SERIES) BY EDXRF

The limited availability of matrix-matched Certified Reference Materials (CRMs) for geological applications necessitates the re-evaluation of legacy standards to ensure their continued analytical fitness. This work validated the performance of Japanese Geological Survey (GSJ) reference materials (JSD-2, JSD-3, and JDO-1) using Energy Dispersive X-ray Fluorescence (EDXRF) combined with Fundamental Parameters (FP) quantification. Calibration curves were established using Weighted Least Squares (WLS) regression to address instrumental sensitivity deviations. While the regression exhibited high linearity ( ) for major oxides, the calibration slopes for light elements deviated significantly from the theoretical unity (Mg ≈ 0.098, Si ≈ 0.64), reflecting uncorrected attenuation losses at low photon energies. Validation using Z-scores demonstrated that the method provided robust accuracy for transition metals and trace elements (Cu, Zn, Pb, Sr) within silicate matrices, yielding satisfactory scores ( ). However, the analysis revealed severe limitations for light elements in non-silicate matrices. This failure indicates a breakdown of the silicate-based calibration model when applied to carbonate lithologies due to differences in mass attenuation coefficients and dark matrix effects. The results confirm that while these legacy CRMs remain reliable for trace element validation in aluminosilicates, accurate quantification of light elements requires strictly matrix-matched calibration strategies.