Fe, Ni, Co, and Cu in FeNi alloys of H Chondrites

Abstract

This publication presents the results of chemical analyses of 173 FeNi alloy grains from four selected H ordinary chondrites: Thuathe, Chergach, Gao-Guenie and NWA 4555. Based on performed analyses and calculations, the following average chemical composition of the FeNi alloy was determined [in wt.%]: Fe - 90.75%; Ni - 8.80%; Co - 0.35%; Cu - 0.03%. The content of Cu and Co depends on the nickel content in the FeNi alloy. The low-nickel alloy represented by kamacite is enriched in cobalt (average content 0.38%) and depleted in copper (0.01%), while the high-nickel alloy, represented mainly by taenite, is characterized by a low content of cobalt (0.08%), and a significant enrichment in copper (0.16%). Based on these data, it is possible to approximate the resources of these metals in the parent bodies of these chondrites. For example, for the asteroid (143624) 2003 HMi6, which is classified as a Near Earth Object (NEO), such resources are [in Mg]: Fe - 2.4 · 109, Ni - 2.3 · 108, Co-9.2 · 106, Cu-7.9 · 105.