Description
Nice full slice weighing 13.2g. Polished on one side. Sold with label/certificate of authenticity./
Northwest Africa 7231 (NWA 7231)
(Northwest Africa)
Purchased: 2011
Classification: HED achondrite (Eucrite, polymict)
Petrography: The individuals are almost completely covered by a partly shiny black fusion crust; the interior appears dark-grayish with visible whitish plagioclase grains. It is composed of basaltic and melt clasts set into a clastic matrix of dominantly exsolved pyroxene and calcic plagioclase. Accessories include chromite, troilite, SiO2, and rare FeNi metal.
Geochemistry: opx: Fs19.8-63.9Wo2.1-6.4, FeO/MnO=27-33; cpx: Fs24.9-225.4Wo42.9-43.8, FeO/MnO=30-31; calcic plagioclase: An91.3 (range 76.7-94.7)
| Place of purchase: | Erfoud, Morocco |
| Date: | P 2011 |
| Mass (g): | 191 |
| Pieces: | 8 |
| Class: | Eucrite-pmict |
| Shock stage: | moderate |
| Weathering grade: | moderate |
| Ferrosilite (mol%): | 19.8-63.9; 24.9-25.4 |
| Wollastonite (mol%): | 2.1-6.4; 42.9-43.8 |
| Classifier: | A. Greshake, MNB |
| Type spec mass (g): | 20.8 |
| Type spec location: | MNB |
| Main mass: | Stefan Ralew |
| Comments: | Submitted by Ansgar Greshake |
