Northwest Africa 12929 (NWA 12929)
Classification: HED achondrite (Eucrite, monomict)
History: Purchased Dec. 2018 by Dustin Dickens in Morocco from anonymous dealer.
Physical characteristics: Many identically appearing pieces, desert weathered exterior, broken surface reveals a dark, fine grained interior.
Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows mild brecciation with approximately 60% pyroxene and 35% plagioclase. Many pyroxenes have exsolution lamellae. Minor silica and troilite observed. Shock melt veins are present.
Geochemistry: (C. Agee, UNM) Low-Ca pyroxene Fs61.6±1.8Wo3.3±2.4, Fe/Mn=32±0, n=9; high-Ca pyroxene Fs36.7±9.5Wo33.4±10.9, Fe/Mn=31±0, n=4; plagioclase An89.4±3.1, n=7.
Classification: Monomict basaltic eucrite, equilibrated.
