Northwest Africa 10327 (NWA 10327)

(Northwest Africa)

Find: 2015

Classification: HED achondrite (Eucrite, melt breccia)

History: Reportedly found in Morocco, 2015 and purchased by Dave Gheesling fom Rachid Chaoui in early 2015.

Physical characteristics: Single stone with weathered fusion-crusted exterior. A saw cut shows a breccia of light-gray and white clasts set in a matrix of dark impact melt, some of it vesicular. A few small caliche-filled cracks and veins are present in the outer rind of the stone, however they do not penetrate throughout the mass.

Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows many fragmental plagioclase and pyroxene grains, and a few microgabbro clasts, bounded by melt veins and pools. Some melt zones transition into a cataclastic groundmass of very fine-grained plagioclase and pyroxene. Most pyroxenes possess exsolution lamellae. Accessory troilite, chromite, ilmenite and silica. Calcite and barite weathering products detected.

Geochemistry: (C. Agee and N. Muttik, UNM) Low-Ca pyroxene Fs_61.7±0.6Wo_2.5±0.7, n=8; high-Ca pyroxene Fs_27.4±0.6Wo_43.1±1.1, n=6; plagioclase An_89.3±2.3, n=4.

Classification: Achondrite (Eucrite, melt breccia) fragmental, equilibrated basaltic eucrite grains set in a eucritic melt rock.

Specimens: 23.6 g including a probe mount on deposit at UNM, Dave Gheesling holds the main mass.