Calibration standards: the Japanese Obsidian Standards (JOS)

The Japanese Obsidian Standards (JOS) are solid obsidian calibration standards developed for quantitative EDXRF analysis of archaeological obsidian. The set consists of 39 geological obsidian samples from Japan and several other countries. Reference values were determined by WDXRF analysis of fused glass beads using a Rigaku Primus III+ at Meiji University, including concentrations of major elements (SiO2, TiO2, Al2O3, Fe2O3t, MnO, MgO, CaO, Na2O, K2O, and P2O5) and trace elements (Zn, Rb, Sr, Y, Zr, Nb, and Th). Each sample has been prepared by polishing a flat surface using #600 grit carborundum for EDXRF analysis.