Northwest Africa 11585 (NWA 11585)

North West Africa, Morocco

Purchased: October 2015

Classification: Ureilite

Petrography: (H. Downes, Birkbeck) Equigranular, anhedral, slightly poikilitic crystals of olivine and low-Ca pyroxene, with minor interstitial metal and very rare carbon. There is no evidence of zoning in minerals. This meteorite does not exhibit a typical ureilite texture, but is more similar to the Hughes Type.

Geochemistry: Mineral compositions and geochemistry: (N. Rai, N.V. Almeida, NHM). All analyses by EPMA. Olivine cores Fa_10.8±0.6, 0.45 to 0.52 wt% MnO, 0.50 to 0.55 wt% Cr₂O₃, 0.14 to 0.68 wt% CaO, < 0.01 wt% Ni, (N=32). Pyroxene Fs_10.1±0.8Wo_8.3±0.6, 0.38 to 0.52 wt% MnO, 0.89 to 0.92 wt% Cr₂O₃, (N=11).

Classification: Ureilite

Specimens: 14.2 g on deposit at the NHM. M. Bilet holds the main mass.