NWA 11157 (29,216 g)

Northwest Africa 11157 (NWA 11157)
(Northwest Africa)
Purchased: 2016
Classification: HED achondrite (Eucrite, brecciated)
History: The meteorite was bought in 2016 from a Moroccan meteorite dealer at a mineral fair in Munich, Germany.
Physical characteristics: Dark grayish individual lacking any fusion crust.
Petrography: The meteorite is a fragmental breccia composed of rare basaltic clasts with different grain sizes and impact melt clasts set into a clastic matrix. Basaltic clasts and matrix are dominantly composed of exsolved pyroxene and plagioclase grains of variable grain sizes ranging from 30 to 500 μm. Several matrix pyroxenes display magmatic zoning. Minor phases include chromite, ilmenite, pyrrhotite, silica and metallic iron.
Geochemistry: low-Ca pyroxene: Fs38.4±7.7Wo6.2±0.6 (Fs29.7-50.8Wo5.1-7.1, n=20, FeO/MnO=25-32); Ca-pyroxene: Fs29.0±4.6Wo38.4±1.1 (Fs19.4-34.1Wo37.0-41.2, n=12, FeO/MnO=25-34); calcic plagioclase: An87.0±4.1 (An73.5-89.5, n=14)
 
Place of purchase:
Munich, Germany
Date:
P 2016
Mass (g):
661
Pieces:
1
Class:
Eucrite-br
Shock stage:
moderate
Weathering grade:
low
Ferrosilite (mol%):
38.4; 29.0
Wollastonite (mol%):
6.2; 38.4
Classifier:
A. Greshake, MNB
Type spec mass (g):
20
Type spec location:
MNB
Main mass:
Philippe Schmitt-Kopplin
Comments:
Submitted by Ansgar Greshake