μ100 Ru for (a) repeat analyses of Ru-Os-Ir alloy B-1 from Witwatersrand, SA; and (b) Shetland Ophiolite Complex chromitites, Os-Ir-Ru alloys, oceanic mantle, CRE corrected IABmg,sLL, and enstatite chondrite group average (from Fischer-Gödde and Kleine, 2017). Filled symbols represent the mean of multiple analyses of the sample. The oceanic mantle composition is the average μ100 Ru composition and the uncertainty reflects an average of the 2SD of repeated analysis of the Alfa Aesar standard from each measurement campaign. The grey fields represent the 2SD of the standards measured during the relevant analytical campaigns. The lowest precision achieved during an analytical session displayed in (b).