Northwest Africa 11377 (NWA 11377)

Mauritania

Find: 2017 May

Classification: Enstatite achondrite (Aubrite)

History: Purportedly found near Ouadane, Mauritania, in May 2017 and subsequently purchased by Habib Naji in Zouerat, Mauritania.

Physical characteristics: The single stone (982 g) is partly coated by black fusion crust, but the interior is white to pale gray in color with some small, stained black grains.

Petrography: (A. Irving and S. Kuehner, UWS) Cataclastic texture (mean grainsize 2.2 mm). Composed predominantly of anhedral grains of pure enstatite with accessory pure forsterite, pure diopside, alabandite (mostly Fe-free but some Fe-bearing), troilite, daubreelite, schreibersite, Si-poor kamacite and taenite.

Geochemistry: Enstatite (Fs_0.0Wo_0.1-0.3, N = 3), forsterite (Fa_0.0), diopside (Fs_0.0Wo_44.6). Kamacite Si 0.04-0.05 wt.%, Ni 3.3-3.8 wt.%, Co 0.32-0.34 wt.% (N = 3).

Classification: Aubrite.

Specimens: 28.7 g including one polished mount at UWB; remainder with Mr. B. Hoefnagels.