Low-temperature exsolution in refractory siderophile element-rich opaque assemblages from the Leoville carbonaceous chondrite

The discovery is reported of opaque assemblages in the Leoville carbonaceous chondrite with both clear textural and chemical evidence of a major role for resolution and equilibration at relatively low temperatures in the formation of refractory siderophile element-rich assemblages. The observed phase compositions are used to bracket a previously inferred phase boundary in the Fe-Ni-Ru system. The first meteoritic occurrence of goldmanite is also reported.