Description
Northwest Africa 14643 (NWA 14643)
(Northwest Africa)
Purchased: 2021
Classification: HED achondrite (Eucrite, polymict)
History: The meteorite was purchased from a meteorite dealer in Erfoud, Morocco.
Physical characteristics: Grayish rock largely covered with fusion crust.
Petrography: The meteorite displays a fresh light grayish interior and is a polymict breccia composed of lithic and mineral clasts set in a fine-grained clastic matrix. Lithic clasts include up to 1.5 cm sized gabbroic, basaltic, and black impact melt clasts. Dominant mineral phases are up to 1 mm sized exsolved pyroxene, compositionally zoned low-Ca pyroxene, and calcic plagioclase grains. Minor phases include silica, chromite, ilmenite, and troilite. No metallic iron detected.
Geochemistry: low-Ca pyroxene: Fs58.5±0.2Wo1.5±0.2 (Fs58.2-58.9Wo1.3-1.9, FeO/MnO=28-34, n=6); augite exsolution lamellae: Fs29.7±0.9Wo37.4±0.3 (Fs29.1-31.7Wo36.9-37.8, FeO/MnO=26-34, n=6); zoned low-Ca pyroxene: Fs40.8±12.5Wo2.1±0.1 (Fs25.8-54.1Wo1.9-2.3, FeO/MnO=29-35, n=4); calcic plagioclase: An90.3±1.6 (An88.8-92.4, n=7)
