Compositional Study of a Suite of Samples from the 28‐t Armanty (Xinjiang) Iron Meteorite

Abstract

Abstract— Neutron activation analysis of 15 samples from widely separated locations on the surface of the 28‐t Armanty (Xinjiang) group‐IIIE iron meteorite showed no compositional variations attributable to magmatic fractionation processes such as fractional crystallization. The homogeneity contrasts with that observed in the Cape York IIIAB iron, in keeping with the idea that the latter is an exceptional case. From the maximum compositional gradients we estimate that the radius of the HIE core was > 1 km. One sample taken from a surface formed by fracture associated with its fall to Earth is slightly anomalous in composition; we suspect that this region is near the border between two parental γ crystals and has a high content of minor phases.