NWA 8658 (Polymict Eucrite)

A 141.4g single stone with a patchy dark brown cracked crust was purchased out of Morocco in November of 2013. Slices were prepared by me and the classification was done by Dr. Paul Warren, who determined the stone to be a Polymict Eucrite. Slices feature an interesting array of clasts set in a light gray groundmass. Each slices comes in a quality labeled meteorite display box.

Petrography as follows:
This meteorite is a polymict eucrite with many distinct, sharply bounded clasts, including one that is uncommonly rich in silica. Minor Fe-metal. Geochemistry: Clasts, and thus mineral compositions, are diverse. Pyroxene compositions extend to En65.1Wo5.6, En35.3Wo2.5, En30.5Wo43.4, En7.5Wo11.5 and En5.5Wo44.5; plagioclase ranges from An71 to An94, minor olivine from Fa62 to Fa87. Averages of the disparate clasts are: low-Ca pyroxene En50.4±12.2Wo7.6±1.7, FeO/MnO wt. ratio 30.1±1.2, n=28; med-Ca pyroxene En27.6±7.0Wo18.5±5.1, n=19; high-Ca pyroxene En20.4±6.5Wo39.0±4.5, n=8; plagioclase An85.0±5.7, n=97; olivine Fa80.3±4.5, n=30.

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