Northwest Africa 8127 (NWA 8127)

(Northwest Africa)

Purchased: 2012 Mar

Classification: Lunar meteorite (gabbro)

History: Purchased by Marc Jost in March 2012 in Brugg, Switzerland from a Moroccan dealer.

Physical characteristics: Fresh, pale green stone (529 g) with cross-cutting thin, black shock veins. Apple green clinopyroxene and glassy maskelynite grains are visible.

Petrography: (A. Irving and S. Kuehner, UWS) Equigranular igneous rock (mean grain size 0.8 mm) consisting of smaller grains of olivine, Ti-bearing chromite and ilmenite (with associated baddeleyite) poikilitically enclosed in clinopyroxene (some containing fine, subparallel exsolution lamellae), with interstitial anorthitic plagioclase. Most plagioclase has been converted to maskelynite, but some grains have patchy birefringence.

Geochemistry: Olivine (Fa_30.0-32.1, FeO/MnO = 90-91), pigeonite (Fs_21.4-25.1Wo_10.6-9.8, FeO/MnO = 46-54), subcalcic augite (Fs_14.5-15.4Wo_32.6-30.5, FeO/MnO = 39-42). Bulk composition (R. Korotev, WUSL) INAA of subsamples gave (in wt.%) FeO 18.2, Na₂O 0.11, and (in ppm) Sc 29.2, La 4.7, Sm 2.59, Eu 0.21, Yb 2.24, Th 0.56.

Classification: Lunar (olivine gabbro). This specimen is paired with NWA 6950 and the gabbroic lithology in NWA 773 and paired stones.

Specimens: 23.7 g, one polished thin section and a polished mount are at UWB. The main mass is held by Space Jewels Switzerland.