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| Northwest Africa 12971 | |||||||||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 12971 This is an OFFICIAL meteorite name. Abbreviation: NWA 12971 Observed fall: No Year found: 2019 Country: (Northwest Africa) Mass:  280 g | ||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 2 approved meteorites classified as Lunar (troct. melt rock). [show all] Search for other: Lunar meteorites | ||||||||||||||||||||||||||||||
| Comments: | Approved 23 Dec 2019 | ||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 108:
Northwest Africa 12971 (NWA 12971) (Northwest Africa) Purchased: 2019 Apr Classification: Lunar (troctolitic melt rock) History: Purchased jointly by Craig Zlimen, Mark Lyon and Matthew Stream in April 2019 from a Moroccan dealer. Physical characteristics: A single light gray stone (280 g) with visible vesicles and light brown weathering products on one side. The fresh interior is composed predominantly of vesicular melt rock which contains some clast-like regions of coarser grained melt rock. Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Very fine-grained (grainsize up to 5 µm), microvesicular melt-textured specimen composed predominantly of anorthite plus subordinate olivine and accessory pigeonite, augite, chromite (exhibiting zoning from Ti-bearing cores to Ti-free rims), troilite and pyrrhotite. No intact clasts were observed anywhere in the entire 5 cm diameter slice examined by microprobe imaging, but there are sporadic coarser-grained (up to 40 µm) melt-textured regions. Geochemistry: Anorthite (An97.2-97.7Or0.0, N = 2), olivine (Fa24.9-35.5, FeO/MnO = 77-99, N = 6), magnesian olivine core (Fa19.0, FeO/MnO = 98), ferroan olivine rim (Fa38.3, FeO/MnO = 80), pigeonite (Fs26.2Wo19.4, FeO/MnO = 44), augite (Fs19.8-35.1Wo35.5±0.0, FeO/MnO = 43-55, N =2). Classification: Lunar (troctolitic melt rock). The predominance of anorthite and olivine indicates a troctolitic bulk composition. The texture and apparent absence of clasts are consistent with crystallization from a totally molten state. Specimens: 22.3 g in the form of a large polished slice at UWB; remainder with Mr. C. Zlimen, Mr. M. Lyon and Mr. M. Stream. | ||||||||||||||||||||||||||||||
| Data from: MB108 Table 0 Line 0: |
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| Institutions and collections |
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, Burke Museum of Natural History and Culture, Box 353010 Seattle, WA 98195, United States (institutional address; updated 9 Oct 2023) |
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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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| Photos: |
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| Geography: |
Statistics: This is 1 of 9699 approved meteorites from (Northwest Africa) (plus 1854 unapproved names) | ||||||||||||||||||||||||||||||
| Also see: |
This lists the most popular meteorites among people who looked up this meteorite.
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| Revision history: |
This lists important revisions made to data for this record.
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