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Northwest Africa 8777 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8777 This is an OFFICIAL meteorite name. Abbreviation: NWA 8777 Observed fall: No Year found: 2013 Country: (Northwest Africa) Mass: 49.1 g | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 160 approved meteorites classified as Achondrite-ung. [show all] Search for other: Achondrites, Ungrouped achondrites | ||||||||||||||||||||||||||||||
Comments: | Approved 27 May 2015 | ||||||||||||||||||||||||||||||
Writeup |
Writeup from MB 104:
Northwest Africa 8777 (NWA 8777) (Northwest Africa) Purchased: 2013 Oct Classification: Ungrouped achondrite History: Purchased by Stefan Ralew in October 2013 from a dealer in Agadir, Morocco. Petrography: (A. Irving and S. Kuehner, UWS) Metamorphic texture with triple grain junctions. Aggregate of predominantly orthopyroxene (88.6 vol.%), olivine (9.0 vol.%) with accessory calcic plagioclase, Al-bearing chromite, Ni-poor kamacite and troilite. Geochemistry: Orthopyroxene (Fs25.5-25.6Wo3.1-2.7, FeO/MnO = 29-34, N = 3), olivine (Fa30.7-31.1, FeO/MnO = 46-49, N = 3), plagioclase (An77.3-78.8Or1.1-0.5, N = 2). Oxygen isotopes (K. Ziegler, UNM): analyses of acid-washed subsamples by laser fluorination gave, respectively, δ17O 1.078, 1.239, 1.257; δ18O 2.659, 2.912, 2.851; Δ17O -0.326, -0.299, -0.248 (all per mil). Classification: Achondrite (ungrouped). Although in texture and oxygen isotopic composition this specimen resembles some brachinites, it is much too orthopyroxene-rich and its constituent plagioclase much too calcic to have an obvious affinity with brachinites. Specimens: 9.9 g including one polished thin section at UWB; main mass with Ralew. | ||||||||||||||||||||||||||||||
Data from: MB104 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) UWB: University of Washington, Burke Museum of Natural History and Culture, Box 353010 Seattle, WA 98195, United States (institutional address; updated 9 Oct 2023) Ralew: Stefan Ralew, Kunibertstraße 29, 12524 Berlin, Germany; 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 9914 approved meteorites from (Northwest Africa) (plus 1841 unapproved names) |