Determination of In and Sn Mass Fractions in Sixteen Geological Reference Materials by Isotope Dilution MC-ICP-MS

Mass fractions of Sn and In were determined in sixteen geological reference materials including basaltic/mafic (BCR-2, BE-N, BHVO-1, BHVO-2, BIR-1, OKUM, W-2, WS-E), ultramafic (DTS-2b, MUH-1, PCC-1, UB-N) and felsic/sedimentary reference materials (AGV-2, JA-1, SdAR-M2, SdAR-H1). Extensive digestion and ion exchange separation tests were carried out in order to provide high yields (> 90% for Sn, > 85% for In), low total procedural blanks (~ 1 ng for Sn, < 3 pg for In) and low analytical uncertainties for the elements of interest in a variety of silicate sample matrices. Replicate analyses (n = 2–13) of Sn–In mass fractions gave combined measurement uncertainties (2u) that were generally < 3% and in agreement with literature data, where available. We present the first high-precision In data for reference materials OKUM (32.1 ± 1.5 ng g−1), DTS-2b (2.03 ± 0.25 ng g−1), MUH-1 (6.44 ± 0.30 ng g−1) and PCC-1 (3.55 ± 0.35 ng g−1) as well as the first Sn data for MUH-1 (0.057 ± 0.010 μg g−1) and DTS-2b (0.623 ± 0.018 μg g−1).