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Northwest Africa 8729 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8729 This is an OFFICIAL meteorite name. Abbreviation: NWA 8729 Observed fall: No Year found: 2014 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 272 approved meteorites classified as Eucrite-mmict. [show all] Search for other: Achondrites, Eucrites, and HED achondrites | ||||||||||||||||||||||||||||
Comments: | Approved 4 Feb 2015 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 104:
Northwest Africa 8729 (NWA 8729) (Northwest Africa) Found: 2014 Classification: HED achondrite (Eucrite, monomict) History: Recovered in April 2014 near the borders of Mauritania, Western Sahara and Algeria. Purchased in Mauritania in June 2014. Physical characteristics: A single stone with irregular exterior. A saw cut reveals white feldspar grains up to 3 mm, green-brown pyroxene grains, all set in a fine-grained light-gray groundmass. Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows approximately equal amounts of pyroxene and plagioclase, slightly brecciated, numerous shock fractures. Accessory troilite, chromite, ilmenite, and silica. Geochemistry: (C. Agee and N. Muttik, UNM). Low-Ca pyroxene Fs55.4±1.5Wo2.1±1.4, Fe/Mn=32±1, n=15; augite Fs24.3±1.4Wo41.8±1.9, Fe/Mn=30±2, n=17; plagioclase An86.2±4.0Ab13.1±3.7Or0.7±0.3, n=5. Classification: Achondrite (eucrite). Equilibrated, clear separation of high-Ca and low-Ca pyroxene, no pigeonite present. Moderate weathering grade, high shock stage. Specimens: 20.7 g including a probe mount on deposit at UNM, DPitt holds the main mass. | ||||||||||||||||||||||||||||
Data from: MB104 Table 0 Line 0: |
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Institutions and collections |
UNM: Institute of Meteoritics
MSC03 2050
University of New Mexico
Albuquerque NM 87131-1126
USA, United States; Website (institutional address; updated 12 Feb 2015) DPitt: Darryl Pitt, 225 West 83rd Street, New York, NY 10024, United States; Website (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
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Geography: |
Statistics: This is 1 of 8904 approved meteorites from (Northwest Africa) (plus 1871 unapproved names) |