Radiogenic 182W abundances of two group IIC irons, corrected for a nucleosynthetic component, indicate a metal-silicate segregation age of 3.2 ± 0.5 Myr subsequent to the formation of Calcium-Aluminum-rich Inclusions (CAI). Abundances of HSE estimated for the parental melt suggest a composition with chondritic relative abundances of HSE ~6 times higher than in bulk carbonaceous chondrites, consistent with the IIC irons sampling a parent body core comprising ~17% of the mass of the body. Variations in highly siderophile element (HSE) abundances among the members of the group can be well accounted for by a fractional crystallization model with all the meteorites crystallizing between ~10 and ~26% of the original melt, assuming initial S and P concentrations of 8 wt.% and 2 wt.%, respectively. The remaining seven IIC iron meteorites exhibit broadly similar bulk chemical and isotopic characteristics, consistent with an origin from a common parent body. Chemical and isotopic data for one, Wiley, indicate that it is not a IIC iron meteorite and should be reclassified as ungrouped. Several of these meteorites were also characterized for mass independent isotopic compositions of Mo, Ru and W. The eight iron meteorites currently classified as belonging to the IIC group were characterized with respect to the compositions of 21 siderophile elements.
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