from The Meteoritical Bulletin, No. 109
Northwest Africa 13283 (NWA 13283)
History: In July 2019, Marc Jost purchased 8 fragments totaling 200.6 g from Aziz Mouadine in Rissani, Morocco.
Physical characteristics: Samples are angular in shape and are coated with a yellowish orange layer of caliche that covers the exterior. The samples have a dark-colored exterior with white-grey, angular clasts. The interior shows light colored brecciated clasts in a dark-colored, micro-vesicular matrix.
Petrography: Sample is a clast-supported breccia composed of: mm-cm-sized, angular micro-gabbroic and rare basaltic lithic fragments; mineral clasts of olivine, exsolved pigeonite, orthopyroxene and anorthite; impact melt breccias; quenched glassy fragments; and schlieren-textured, micro-vesicular glassy breccias (agglutinates) set within a fine-grained matrix. Additional minerals include: ilmenite, chromite, FeNi fragments and troilite.
Geochemistry: (A. Love, App) Olivine (Fa9.5-53.6, Fe/Mn=72.4-89.2, n=12), low-Ca pyroxene (Fs26.4-54.2Wo2.0-4.7, Fe/Mn=53.0-60.3 n=8), pigeonite (Fs30.5-39.7Wo7.6-18.0), high-Ca pyroxene exsolution lamellae (Fs12.9-27.9Wo36.9-41.4, n=9), plagioclase (An96.4-98.3Or0.0, n=10).
Classification: Lunar (anorthosite regolith breccia). Fe/Mn ratios in and pyroxene and anorthite compositions suggest this is a lunar sample. Textures and mineralogy suggest sample is an anorthositic regolith breccia.
Specimens: Marc Jost (SJS) holds the main masses. A polished thin section and mount and fragment weighing 20.1 g are on deposit at App.
I have not analyzed NWA 13283. It might be another pair of the NWA 8046 clan.
Meteoritical Bulletin Database