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Northwest Africa 12775 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 12775 This is an OFFICIAL meteorite name. Abbreviation: NWA 12775 Observed fall: No Year found: 2011 Country: (Northwest Africa) Mass: 51.5 g | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 595 approved meteorites (plus 1 unapproved name) classified as Eucrite. [show all] Search for other: Achondrites, Eucrites, and HED achondrites | ||||||||||||||||||||||||||||
Comments: | Approved 11 Oct 2019 | ||||||||||||||||||||||||||||
Writeup |
Writeup from MB 108:
Northwest Africa 12775 (NWA 12775) (Northwest Africa) Purchased: 2011 Classification: HED achondrite (Eucrite) History: Cataloged in the ROM collection as LM55993. Physical characteristics: The meteorite has a well-preserved, dark fusion crust, with no evident weathering. Interior of the meteorite intact, uniform and pale gray, with visible thin, black veins and very-fine grained texture. Petrography: Fine-grained basalt, with equilibrated texture, slightly brecciated. A small vein that appears to be of impact origin. The sample contains a small clast that shows thermal disequilibration. Very fine grained plagioclase and pyroxene in the matrix, with seldom large laths of plagioclase and subordinate large pyroxene grains. Matrix plagioclase needle-shaped. Geochemistry: Mineral composition and geochemistry: Plagioclase, An89.5±2.2 (n=18). Low-Ca pyroxene composition: Fs42.7±1.6Wo4.6±1.9 and Mg# 34.5-36.7 (n=8); high-Ca pyroxene composition: Fs24.1±8.6Wo38.1±15.3, Mg# 38.2-52.2 (n=10) Classification: (A. Cernok, ROM) Sample is an equilibrated basaltic eucrite. Texture and compositions suggest the sample has experienced thermal equilibration. | ||||||||||||||||||||||||||||
Data from: MB108 Table 0 Line 0: |
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Institutions and collections |
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011) DGregory: David Gregory, 230 First Avenue, Suite 108, St. Thomas, Ontario N5R 4P5, Canada (private address) |
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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 9589 approved meteorites from (Northwest Africa) (plus 1869 unapproved names) | ||||||||||||||||||||||||||||
Also see: |
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Revision history: |
This lists important revisions made to data for this record.
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