The study of chemical composition of 35 iron meteorites and its application in taxonomy

Reported in this paper are structural and compositional data as the basis for the classification of 35 iron meteorites. The Xingjiang iron meteorite, previously labelled IIIAB, is reclassified as IIIE on the basis of its lower Ga/Ni and Ge/Ni ratios, its wider and swollen kamacite bands and the ubiquitous presence of haxonite, (Fe, Ni)₂₃C. IIICD Dongling appears not to be a new meteorite, but to be paired with Nandan. Four Antarctic iron meteorites IAB Allan Hills A77250, A77263, A77289 and A77290 are classified as paired meteorites based on their similarities in structure, and the concentrations of Cr, Co, Ni, Cu, Ga, Ge, As, Sb, W, Re, Ir and Au. It is found that Cu shares certain properties with Ga and Ge, which makes it an excellent taxonomic parameter. BecauseK _Cu is near unity, Cu displays a small range of variation within most magmatic groups (less than a factor of 2.2) and, because of its high volatility, large variations can be noticed among groups.