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Northwest Africa 12911 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 12911 This is an OFFICIAL meteorite name. Abbreviation: NWA 12911 Observed fall: No Year found: 2003 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 12583 approved meteorites (plus 8 unapproved names) classified as L6. [show all] Search for other: L chondrites, L chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||
Comments: | Approved 26 Sep 2019 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 108:
Northwest Africa 12911 (NWA 12911) (Northwest Africa) Purchased: 2003 Classification: Ordinary chondrite (L6) History: Baird purchased at a meteorite auction in Tucson in 2003, and donated an end piece to Cascadia in 2013. Physical characteristics: The exterior of the end piece is covered by a dark brown/black fusion crust and is faceted. The cut face is polished; most of the face is dark brown, lacks readily defined chondrules, and contains almost no visible metal/sulfide grains. One side of the cut face is light gray and contains moderately abundant metal/sulfide grains. Petrography: (M. Hutson, A. Ruzicka, W. Fish, Cascadia): The texture of the silicates in thin section are relatively well-integrated; indistinct chondrules are visible. Plagioclase feldspar grains up to 70 microns across are present. Approximately 60-70% of metal and sulfide grains have been replaced. Geochemistry: Mineral compositions and geochemistry: Olivine and pyroxene grains are equilibrated: Fa25.7±0.5, N=14; Fs21.4±0.1Wo1.6±0.2, N=13. Classification: Ordinary chondrite (L6) based on chemistry and texture. Specimens: Cascadia holds 22.2 g in two pieces, in addition to two polished thin sections and a mounted butt. The main mass is held by Baird: Jerry Baird, Lake Havasu City, AZ. | ||||||||||||||||||||||||||||
Data from: MB108 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) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 108 (2020) Meteorit. Planet. Sci. 55, 1146-1150
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |