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Northwest Africa 12205 | |||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 12205 This is an OFFICIAL meteorite name. Abbreviation: NWA 12205 Observed fall: No Year found: 2013 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||
Classification history: |
This is 1 of 630 approved meteorites classified as Ureilite. [show all] Search for other: Achondrites, Ureilites | ||||||||||||||||||||||||||
Comments: | Approved 7 Mar 2019 | ||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 108:
Northwest Africa 12205 (NWA 12205) (Northwest Africa) Purchased: 2013 Feb Classification: Ureilite Physical characteristics: Puck-shaped, dark-brown stone with remnant fusion crust on approx. half the surface. Remaining surface is broken with minor caliche and rust spots in some areas. Sample includes a polished thin section and billet. Petrography: Sample is characterized by a lack of a reduction rim around olivine, as well as abundant low-Ca pyroxene. Triple junctions are observed throught the sample and an opaque phase interfills 100-200 μm silicates. Low-Ca pyroxenes form 3 mm sized aggregates. Porphyroblastic Ca-rich pyroxene is present. Modal abundances: olivine approx. 60%; low-Ca pyroxenes approx. 30%; remainder is opaque material. Geochemistry: Olivine core: Fa12.4±0.1 FeO/MnO = 21.88±1.38 (n=6). Augite: Fs6.6±0.2Wo36.9±0.2, (n=8). Pigeonite: Fs10.9±0.1Wo4.7±0.1, (n=4). δ17O = 3.771 permil, δ18O = 8.206 permil, Δ17O = -0.877 permil. | ||||||||||||||||||||||||||
Data from: MB108 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||
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) OkaU: Institute for Study of the Earth's Interior, Okayama University, Misasa Tottori 682-0193, Japan (institutional 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 9116 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |