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Northwest Africa 12431 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 12431 This is an OFFICIAL meteorite name. Abbreviation: NWA 12431 Observed fall: No Year found: 2016 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 469 approved meteorites classified as LL3. [show all] Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||
Comments: | Approved 16 Feb 2019 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 108:
Northwest Africa 12431 (NWA 12431) (Northwest Africa) Purchased: 12 Dec 2016 Classification: Ordinary chondrite (LL3) Physical characteristics: Exterior surfaces of the type specimen are bumpy and covered with patches of brown-colored remnant fusion crust and light tan caliche. Interior surfaces are bluish-gray, with well-defined chondrules and abundant sulfide with some metal. One cut face shows a 6x3.5mm dark clast. Petrography: (M. Hutson, A. Ruzicka, Cascadia) In thin section, the sample contains chondrules with a variety of sizes and textures, including some that are rimmed by sulfide. Along the edge of the section is a roughly triangular shaped clast (base approximately 4.9 mm × height approximately 4.9 mm), with a spinifex texture, consisting of acicular olivine set in a feldspathic matrix. Geochemistry: Mineral compositions and geochemistry: (M. Hutson, R. Kostynick, A. Ruzicka, Cascadia) Host olivine (Fa26.4±4.1, N=29, Fa coefficient of variation = 15.6); low-Ca pyroxene (Fs16.2±7.2Wo0.7±0.5, N=31). Classification: LL3. Estimated subtype 3.8. Specimens: Cascadia holds 17.7 g in three pieces, in addition to a polished thin section. | ||||||||||||||||||||||||||||
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) |