NWA 14637 ( 13,612 g )

Northwest Africa 14637 (NWA 14637)
Howardite, (Northwest Africa)
Purchased: 2021 Dec
Classification: HED achondrite (Howardite)
History: The meteorite was purchased from a meteorite dealer in Morocco.
Physical characteristics: Grayish rock mostly covered with fusion crust.
Petrography: The meteorite is a polymict breccia composed of a variety of mineral and lithic fragments set into a fine-grained clastic groundmass. Lithic fragments are up to 7 mm sized basaltic, gabbroic and black impact melt clasts. Predominant minerals are Fe-rich low-Ca pyroxenes with augite exsolution lamellae, diogenitic low-Ca pyroxene (about 20 vol%), ferroan unexsolved low-Ca pyroxene, and calcic plagioclase all with highly variable grain sizes. Diogenetic low-Ca pyroxenes are up to 700 µm in size. Minor phases include silica, Ti-poor chromite, ilmenite, FeS, and metallic iron.
Geochemistry: low-Ca pyroxene host to augite exsolution lamellae: Fs61.1±0.7Wo2.1±0.2 (Fs60.6-62.8Wo1.7-2.4, FeO/MnO=29-33, n=7); augite exsolution lamellae: Fs21.8±0.1Wo43.6±0.3 (Fs21.5-21.9Wo43.3-44.1, FeO/MnO=27-31, n=7); diogenetic pyroxene: Fs23.4±0.3Wo2.0±0.4 (Fs22.9-23.7Wo1.7-3.0, FeO/MnO=27-34, n=7); ferroan unexsolved low-Ca-pyroxene: Fs42.1±1.0Wo2.7±1.1 (Fs40.5-43.1Wo1.8-4.5, FeO/MnO=28-31, n=7); calcic plagioclase: An90.0±0.8 (An89.2-91.9, n=7)
 
State/Prov/County:
Howardite
Place of purchase:
Morocco
Date:
P 2021 Dec
Mass (g):
244.2
Pieces:
1
Class:
Howardite
Shock stage:
low
Weathering grade:
low
Ferrosilite (mol%):
61.8; 21.8; 23.4; 42.1
Wollastonite (mol%):
2.1; 43.6; 2.2; 2.7
Classifier:
A. Greshake, MNB
Type spec mass (g):
21.6
Type spec location:
MNB
Main mass:
Hanno Strufe
Comments:
Submitted by Ansgar Greshake