Development of a Matrix‐Matched Sphalerite Reference Material (MUL‐ZnS‐1) for Calibration of In Situ Trace Element Measurements by Laser Ablation‐Inductively Coupled Plasma‐Mass Spectrometry

Sphalerite (ZnS) is an abundant ore mineral and an important carrier of elements such as Ge, Ga and In used in high-technology applications. In situ measurements of trace elements in natural sphalerite samples using LA-ICP-MS are hampered by a lack of homogenous matrix-matched sulfide reference materials available for calibration. The preparation of the MUL-ZnS1 calibration material containing the trace elements V, Cr, Mn, Co, Ni, Cu, Ga, Ge, As, Se, Mo, Ag, Cd, In, Sn, Sb, Tl and Pb besides Zn, Fe and S is reported. Commercially available ZnS, FeS, CdS products were used as the major components, whereas the trace elements were added by doping with single-element ICP-MS standard solutions and natural mineral powders. The resulting powder mixture was pressed to pellets and sintered at 400 °C for 100 h using argon as an inert gas. To confirm the homogeneity of major and trace element distributions within the MUL-ZnS1 calibration material, measurements were performed using EPMA, solution ICP-MS, ICP-OES and LA-ICP-MS. The results show that MUL-ZnS-1 is an appropriate material for calibrating trace element determination in sphalerite using LA-ICP-MS.