Evidence of a deep mantle history in terrestrial osmium-iridium- ruthenium alloys.

Abstract

It is suggested that Os-Ir-Ru alloys found in placers derived from peridotites of obducted ophiolites come from the primitive mantle, possibly as deep as the core-mantle boundary, and that the alloys were originally primitive material which has remained essentially intact since accretion of the Earth from the solar nebula.M.J.Le B.