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Northwest Africa 12264 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 12264 This is an OFFICIAL meteorite name. Abbreviation: NWA 12264 Observed fall: No Year found: 2018 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 88 approved meteorites classified as Achondrite-ung. [show all] Search for other: Achondrites, Ungrouped achondrites | ||||||||||||||||||||||||||||||
Comments: | Approved 5 Jan 2019 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 108:
Northwest Africa 12264 (NWA 12264) (Northwest Africa) Purchased: 2018 Aug Classification: Ungrouped achondrite History: Purchased by Ben Hoefnagels in August 2018 from a dealer in Agadir, Morocco. Petrography: (A. Irving and S. Kuehner, UWS; P. Carpenter, WUSL) Breccia composed almost entirely (>95 vol.%) of closely packed, angular grains of olivine (some up to 9 mm across, exhibiting undulose extinction) in a sparse olivine-rich matrix containing minor chromite, low-Ca pyroxene, plagioclase and rare exsolved pigeonite. Some symplectitic intergrowths of chromite and pyroxene are also present. Geochemistry: Olivine (Fa20.8-22.0, FeO/MnO = 74-88, N = 4), low-Ca pyroxene (Fs17.6-17.7Wo4.8-4.3, FeO/MnO = 64-69, N = 2), clinopyroxene host in exsolved pigeonite (Fs26.6Wo39.6, FeO/MnO = 51), orthopyroxene exsolution lamella (Fs53.1Wo4.5, FeO/MnO = 69), plagioclase (An51.8Or2.6). Oxygen isotopes (K. Ziegler, UNM): Analyses of acid-washed subsamples by laser fluorination gave, respectively, δ17O -2.886, -3.489, -3.605; δ18O 0.467, -0.028, -0.092; Δ17O -3.133, -3.474, -3.557 per mil. Classification: Achondrite (ungrouped, dunitic breccia). Oxygen isotopes plot close to the values for the Milton pallasite (Jones et al., 2003) and between the trends for CR chondrites and CV chondrites. Specimens: 10.4 g including one polished thin section at UWB; remainder with Mr. B. Hoefnagels. | ||||||||||||||||||||||||||||||
Bibliography: |
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Data from: MB108 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||||
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) UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012) WUSL: Washington Univ., One Brookings Drive, St. Louis, MO 63130, United States (institutional address; updated 17 Oct 2011) UWB: University of Washington, Box 353010 Seattle, WA 98195, United States (institutional address; updated 27 Jul 2012) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 108, in preparation (2019)
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Geography: |
Statistics: This is 1 of 7048 approved meteorites from (Northwest Africa) (plus 1998 unapproved names) |