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| Northwest Africa 12749 | |||||||||||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 12749 This is an OFFICIAL meteorite name. Abbreviation: NWA 12749 Observed fall: No Year found: 2019 Country: (Northwest Africa) Mass:  497 g | ||||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 451 approved meteorites classified as Howardite. [show all] Search for other: Achondrites, HED achondrites, and Howardites | ||||||||||||||||||||||||||||||||
| Comments: | Approved 26 Sep 2019 | ||||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 108:
Northwest Africa 12749 (NWA 12749) (Northwest Africa) Purchased: 2019 Classification: HED achondrite (Howardite) History: Two stones weighing 497.29 g were found in Western Sahara prior to 2019. John Sinclair and J. Donald Cline purchased the samples from a meteorite dealer while at the 2019 Tucson Gem and Mineral Show. Physical characteristics: The sample has a light orangish-brown exterior with a distinctive brecciated texture. The samples lack fusion crust. Dark brown to dark-greenish clasts up to 4 cm are visible on the exterior of the stone. Petrography: Description and classification (A. Love, App): Sample is a breccia composed of rounded to angular dominant mineral and subordinate lithic fragments with an average diameter of 2.7 mm and some as large as 4 cm. Diogenite (~60 vol%) occurs primarily as zoned crystals and fragments of Opx, although a rare lithic fragment shows interlocking crystals that share 120º grain boundaries. Eucrites (~40 vol%) occur as basaltic and cumulate lithic fragments as well as individual twinned plagioclase and exsolved Cpx crystals. Other phases include pyroxene rimmed silica objects, FeNi metal, FeS, and chromite. Geochemistry: (A. Love, App) Diogenite clasts: low Ca pyroxene Fs31.0±2.4Wo1.9±0.4 (Fs26.5-34.0Wo1.2-2.9), Fe/Mn=31.1±1.5, N=20. Eucrite clasts: low Ca pyroxene Fs34.8±3.4Wo2.1±0.4 (Fs28.0-41.5Wo1.5-2.7), Fe/Mn=29.7±4.9, Mg#57.5-71.4, n=18; high Ca pyroxene exsolution lamellae Fs15.8±1.4Wo42.1±0.7 (Fs13.0-17.6Wo41.4-43.6), Fe/Mn=23.0±3.9, N=10; plagioclase An92.5±2.0Or0.3±0.1, N=8. Classification: HED (Howardite). Textures, FeO/MnO and Fs compositions of pyroxenes indicate this sample belongs to the HED meteorites. Sample is a howardite with a subequal mixture of eucrite and diogenite. Specimens: PARI holds the main mass. One endcut weighing 21.59 g and a polished mount are on deposit at App. | ||||||||||||||||||||||||||||||||
| Data from: MB108 Table 0 Line 0: |
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| Institutions and collections |
App: Department of Geology, 572 Rivers St., Appalachian State University, Boone, NC 28608, United States (institutional address; updated 7 Mar 2013) PARI: Pisgah Astronomical Research Institute 1 Pari Dr Rosman, NC 28772, United States (institutional address; updated 13 Sep 2016) |
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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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| 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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