The Meteoritical Bulletin, No. 99
Mass: 1638 g
History: A tan to gray 1638 g stone was purchased in Morocco by
Adam Aaronson in 2010.
is deeply etched in some places from desert wind abrasion, and the gray
colored areas show remnant, translucent fusion crust.
Petrography: (T. Bunch and J. Wittke, NAU; A.
Irving and S. Kuehner, UWS):
A fine-grained (<0.5 mm, mean grain size = 0.125 mm) partially annealed ultracataclastite (crushed matrix occupies > 90
vol%). The rock is an anorthosite based on the mineral modes of (vol%):
anorthite 90, pigeonite 6, olivine 2, metal and FeS2. Numerous fine-grained
(<0.02 mm) micrographic-textured patches contain pigeonite + olivine +
plagioclase ± FeS and are roughly flow-oriented.
In addition, glassy shock melt veins are sub parallel to the apparent flow
direction. A few elongated clusters of vermiform taenite
(<0.05 mm) are interspersed with micrographic intergrowths.
Geochemistry: Plagioclase, An94-96.3; pigeonite, Fs27.7-33.4Wo12.4-14,
(FeO/MnO = 73-98); olivine, Fa21.7-44 (FeO/MnO = 78-90); taenite
Ni = 9.8-16.7 wt. %. Shock melt glass (avg. of 3 in wt%) is SiO2
= 45.2, Al2O3 = 28.8, CaO = 18.9, FeO = 3.86, MgO =
2.12, Na2O = 0.4, TiO2 = 0.47, MnO = 0.18.
Classification: Achondrite (lunar, granulitic anorthositic breccia).
This meteorite is one of the most feldspar-rich lunar specimens (rivaling
some Apollo samples), but is texturally unique.
Specimens: A total of 20.2 g is on deposit at NAU. Mr.
holds the main mass.