Northwest Africa 11428 (NWA 11428)

(Northwest Africa)

Purchased: 2017 Aug

Classification: Lunar meteorite (feldspathic breccia)

History: Purchased by Bob Falls in July 2017 from dealer in Zagora, Morocco.

Physical characteristics: The stones lack fusion crust but are thinly coated by reddish-brown weathering products. The fresh interiors exhibit white to beige, angular clasts in a medium gray matrix.

Petrography: (A. Irving and S. Kuehner, UWS) Breccia composed of angular mineral clasts of anorthite, exsolved pigeonite, olivine, ilmenite, Ti-chromite, troilite and kamacite in a finer matrix containing sporadic small vesicles.

Geochemistry: Olivine (Fa18.8-56.2, FeO/MnO = 87-96, N = 3), pigeonite (Fs37.8Wo7.6, FeO/MnO = 54), augite (Fs7.5Wo44.2, FeO/MnO = 29), augite host (Fs24.2Wo40.7, FeO/MnO = 66), low-Ca pyroxene exsolution lamella (Fs51.0Wo5.0, FeO/MnO = 65), plagioclase (An97.1-97.2Or0.2, N = 2).

Classification: Lunar (feldspathic breccia).

Specimens: 20.71 g including one polished endcut at UWB; remainder with Mr. B. Falls.