Allabogdanite, the high-pressure polymorph of (Fe,Ni)2P, a stishovite-grade indicator of impact processes in the Fe-Ni-P system.

ABSTRACT: Allabogdanite, (Fe,Ni)2P, is the only known natural high-pressure phase reported in the Fe-Ni-P system. The mineral, which was previously described from a single meteorite, the Onello iron, is now discovered in the Santa Catharina and Barbianello nickel-rich ataxites. The occurrence of allabogdanite in Santa Catharina, one of the largest and well-studied meteorites, suggests that this mineral is more common than was believed. The formation of allabogdanite-bearing phosphide assemblages in a given meteorite provides evidence that it experienced peak pressure of at least 8?GPa at a temperature above 800?°C. Since the pressure-temperature stability parameters of allabogdanite fall within the margins of the stishovite (rutile-type SiO2) stability area, the former can be employed as a convenient stishovite-grade indicator of significant impact events experienced by iron and stony-iron meteorites and their parent bodies.

SUBMITTER: Britvin SN 

PROVIDER: S-EPMC6355872 | biostudies-other | 2019 Jan

REPOSITORIES: biostudies-other