Northwest Africa 8277 (NWA 8277)

(Northwest Africa)

Purchased: 2013

Classification: Lunar meteorite

History: Purchased by Adam Aaronson in Morocco, 2013.

Physical characteristics: Single stone, no fusion crust, irregular sandblasted exterior with numerous light- and dark-colored clasts. Saw cut reveals brecciated texture with white feldspar and green-brown pyroxene and olivine grains (up to 3 mm) set in a dark gray-green matrix.

Petrography: (C. Agee, UNM) Microprobe examination of polished mount shows a fragmental breccia of plagioclase, pyroxene, and olivine grains in a wide range of grain sizes. The groundmass is variable with some domains showing a uniform fine-grained subophitic plagioclase-pyroxene texture, while other domains show densely packed mineral clasts ranging from 10-300 μm. There are several sharp boundaries between the various textural domains, with at least two compositionally distinct olivine populations, and a wide range of pyroxene compositions, indicating multiple lithologies of a mingled fragmental breccia. Accessory ilmenite, silica polymorph, and troilite.

Geochemistry: (C. Agee, UNM). Fayalitic olivine grain Fa_92.0, Fe/Mn=92; forsteritic olivine Fa_41.1±11.8, Fe/Mn=103±8, n=9; pyroxene Fs_40.5±12.9Wo_22.4±9.4, Fe/Mn=65±9, n=63; plagioclase An_90.9±7.2Ab_8.6±6.8Or_0.5±0.5, n=30.

Classification: Achondrite (lunar breccia), comparison of macroscopic and backscatter-electron textures, geochemistry of pyroxenes, olivines, and plagioclase, indicate that this meteorite is likely paired with NWA 7611.

Specimens: A total of 21 g including a probe mount on deposit at UNM. Aaronson holds the main mass.