The Sychevka IIIAB iron meteorite: A new find from Russia

Abstract

Abstract-Sychevka is a relatively unweathered 65-kg iron meteorite that was found in Russia in 1988. The microstructure, mineralogy and bulk composition ofSychevka as revealed by optical microscopy, electron microprobe and instrumental neutron activation analysis indicate that this meteorite is a group-IIIAB medium octahedrite. Sychevka consists of (in vol%): kamacite (82.5), plessite (16), schreibersite (1.5), and rare grains of chromite and troilite.

Unusual large chromite crystals in the Saint Aubin iron meteorite

“…This is confirmed by the composition of Saint Aubin chromite, which is close to the composition of pure endmember chromite as shown in Table 1. Similar pure chromite was also reported from the Sychevka octahedrite (Krot et al 1992), where it is enclosed in the metal phase similar to the Saint Aubin meteorite. The Sychevka chromite contains only minor amounts of vanadium (0.09 wt% V 2 O 3 ; Table 2) but displays appreciable amounts of zinc (0.77 wt% ZnO; Table 1) in contrast with the Saint Aubin chromite.…”

“…The average of 20 measurements is given in Table 1 (Krot et al 1992). d Chromite adjacent to shock veins in Suizhou chondrite (Chen et al 2003).…”

A petrological and chemical reexamination of Main Group pallasite formation

“…Square symbols are chromite averages from Bunch and Keil (1971). and MgO (0.01-0.06 wt%) (Krot et al, 1992;Fehr and Carion, 2004). IIIAB chromites, unlike pallasite chromites, reflect formation in an environment where a silicate melt was distinctly absent.…”

Coexistence pressure for a martensitic transformation from theory and experiment: Revisiting the bcc-hcp transition of iron under pressure

“…Thus, magneto-structural transformations and high-pressure states in iron attract enormous interest, especially in geophysics because iron is a primary constituent of the Earth's core, 29−163 many meteorites, [163][164][165][166][167][168][169][170][171][172] and, due to its properties and availability, most steels. 173 At low pressure P and temperature T , the α-phase of iron is a ferromagnet (FM) with the body-centered cubic (bcc) structure.…”