Terrestrial alloys of osmium-iridium-ruthenium occur in places from depleted mantle of obducted ophiolites. Some specimens consist of intergrown metal phases having textures and compositions consistent with formation by crystallization from a melt at temperatures greater than various proposed geotherms of the earth's mantle. It is proposed that these specimens were subjected to melting in the lower mantle when the earth had temperatures higher than at present or that they melted at depths greater than 2900 km before that region was occupied by the core or that they once resided within the core. The alloys were probably transported in convecting mantle material and were subsequently incorporated into depleted mantle of lithosphere, now exposed as obducted ophiolites. It is further proposed that the alloys were originally primitive material that has remained essentially intact since accretion of the earth from the solar nebula.