Itqiy meteorite

The Itqiy meteorite is an enstatite-rich stony-iron meteorite. It is classified as an enstatite chondrite of the EH group that was nearly melted and is therefore very unusual for that group. Other classifications have been proposed and are an ongoing scientific debate.

History

Itqiy fell during 1990 in Western Sahara and is named after a small hamlet. One stone was recovered soon after by a nomad, a second stone was recovered in July 2000 by Marc, Luc, and Jim Labenne who were searching for meteorites in the same location. It was first described in 2001.

Mineralogy and petrology

Itqiy is a stony-iron meteorite consisting of 78% enstatite and 22% meteoric iron. The meteoric iron is kamacite with 5.77% nickel. Small amounts of other minerals include troilite, Mg-Mn-Fe sulfides and Fe-Cr sulfides.

Classification

The meteorite was described as an "Enstatite meteorite ungrouped" in 2001. It was reasoned that Itqiy represents a rock that formed through partial melting of an enstatite chondrite. In 2006 Itqiy was classified as a member of the EH group, petrologic type 7, emphasizing the strong metamorphic overprint of the specimen. In 2008 it was argued that Itqiy represents the residue of an enstatite chondrite that was partially molten about 20%, thereby removing the plagioclase. In 2011 it was proposed that Itqiy, QUE 94204, QUE 97289, QUE 97348, NWA 2526 and possibly Yamato 793225 are part of a new group that should be called "primitive enstatite achondrites".