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Northwest Africa 8643 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8643 This is an OFFICIAL meteorite name. Abbreviation: NWA 8643 Observed fall: No Year found: 2002 Country: (Northwest Africa) Mass: 8 g | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 13099 approved meteorites (plus 11 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 15 Nov 2014 | ||||||||||||||||||||||||||||||
Writeup |
Writeup from MB 103:
Northwest Africa 8643 (NWA 8643) (Northwest Africa) Purchased: 2002 Feb Classification: Ordinary chondrite (L6) History: Purchased February 2002 at the Gem and Mineral show in Tucson by Edwin Thompson from a Moroccan trader. Donated to Cascadia on May 24, 2002. Physical characteristics: Small medium gray specimen completely lacking fusion crust, with numerous dark grains protruding from surface often surrounded by rust halos. Petrography: (K. Farley, A. Ruzicka, Cascadia) Thin section reveals granoblastic texture with well-integrated chondrules. Rust staining occurs in clumps around some metal and sulfide grains. Individual chondrules are difficult to distinguish, but the 7 most distinct have a mean chondrule diameter of ~0.45 mm. Roughly 10% of the metal has been weathered. Geochemistry: Olivine (Fa25.5±0.2, N=20), low-Ca pyroxene (Fs21.5±0.2Wo1.5±0.2En77.0±0.2, N=22), high-Ca pyroxene (Fs7.5±0.8Wo45.5±1.0En47.0±0.3, N=6), feldspar (Ab82.6±1.0Or6.6±0.9An10.8±0.1, N=4). Classification: L6 chondrite based on mineral chemistry and texture. Specimens: Cascadia holds the entire sample which includes 6.4 g in two pieces, 1 polished thin section, and 1 butt. | ||||||||||||||||||||||||||||||
Data from: MB103 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. 103, MAPS 52, 1014, May 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12888/full
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Geography: |
Statistics: This is 1 of 9933 approved meteorites from (Northwest Africa) (plus 1837 unapproved names) |