Determination of Major and Trace Elements in Japanese Rock Reference Samples by ICP-MS

Abstract

Analysis were made, using inductively coupled plasma-mass spectrometry (ICP-MS), to measure 59 major and trace elements in 6 rock reference samples, JB-1, JB-3. JG-1, JR-2, JGb-1 and JA-2, prepared and distributed by the Geological Survey of Japan (GSJ). Sample preparation and analytical conditions were investigated to set up a simple routine procedure for measuring a large range of elements. Detection limits, reproducibility. accuracy, dilution factors, possible interferences, and stability of standard solutions were also studied. For a prompt sample decomposition, a microwave digestion technique was successfully used with an acid mixture of HF, HCIO₄ and HNO₃. Low background counts and the high sensitivity of ICP-MS provided extremely low detection limits for most elements (0.2–2 ng/l). Precisions were typically better than 5% RSD (relative standard deviation). Generally, the ICP-MS data presented here agreed well with the published GSJ consensus values. In about 40 elements, errors of measured values were less than 10% of the certified values, and for 52 elements, errors were less than 30%.