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Northwest Africa 7908 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 7908 This is an OFFICIAL meteorite name. Abbreviation: NWA 7908 Observed fall: No Year found: 2004 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 518 approved meteorites classified as Diogenite. [show all] Search for other: Achondrites, Diogenites, and HED achondrites | ||||||||||||||||||||||||||||
Comments: | Approved 27 Jul 2013 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 102:
Northwest Africa 7908 (NWA 7908) (Northwest Africa) Purchased: Feb 2004 Classification: HED achondrite (Diogenite) History: A pre-cut specimen was purchased from a Moroccan trader by Edwin Thompson, and a portion was donated to Cascadia, in February, 2004. Physical characteristics: A cut slab shows grey clasts ranging from <1 mm to 1.5 cm set in a light-brown matrix. Black clasts are also present. Rust halos surround sparse metal grains in the matrix. The surface of the sample is rough, light brown to grey to black, and mostly lacks fusion crust. Petrography: (A. Ruzicka, Cascadia) In thin section the meteorite consists almost entirely of low-Ca pyroxene and chromite. Coarse-grained (1-2 mm) orthopyroxenite (gray) and chromite (black) clasts are set in a matrix of smaller pyroxene and chromite clasts. Grains are highly fractured and pyroxene shows undulose to mosaic extinction. One metal grain is partly replaced by weathering product. Geochemistry: Phase compositions are highly equilibrated: low-Ca pyroxene Wo1.6±0.1 Fs25.1±0.8 Fe/Mn =26.5±2.7 (N=37), chromite Cr/(Cr=Al) = 0.83± 0.01 Fe/(Fe+Mg)= 0.78± 0.02 (N=14) (atomic units). Classification: Achondrite (diogenite). Textures and mineralogy suggest a monomict orthopyroxenitic breccia. Minor weathering. Specimens: 27.0 g, one polished thin section, and one butt are on deposit at Cascadia. Thompson holds the main mass. | ||||||||||||||||||||||||||||
Data from: MB102 Table 0 Line 0: |
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Institutions and collections |
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011) Thompson: Edwin Thompson, 5150 Dawn St., Lake Oswego, OR 97035, United States (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 102, MAPS 50, 1662, September 2015
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |