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Northwest Africa 2177 | |||||||||||||||||
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Basic information | Name: Northwest Africa 2177 This is an OFFICIAL meteorite name. Abbreviation: NWA 2177 Observed fall: No Year found: 2003 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||
Classification history: |
This is 1 of 587 approved meteorites (plus 1 unapproved name) classified as Eucrite. [show all] Search for other: Achondrites, Eucrites, and HED achondrites | ||||||||||||||||
Comments: | Approved 28 Mar 2007 | ||||||||||||||||
Writeup![]() |
Writeup from MB 91:
Northwest Africa 2177 Northwest Africa Find: 2003 Achondrite (eucrite) History: Several stones were found by an anonymous finder in the western part of the Sahara and purchased by M. Chinellato in Erfoud, Morocco, in 2003. Physical characteristics: The total mass is 74.8 g. The largest mass, weighing 21 g, has no fusion crust and appears dark gray on its surface. Petrography: (V. Moggi Cecchi and G. Pratesi, MSP) A polymict breccia consisting of basaltic and mineral clasts set into a fine-grained matrix of exsolved Ca pyroxene and plagioclase. The large clasts are predominantly plagioclase and exsolved low-Ca pyroxene. Minor phases include silica and Al chromite. Exsolution lamellae in pyroxene are generally very fine. Mineral compositions and geochemistry: Plagioclase (An89), orthopyroxene (Fs53En44Wo2), pigeonite (Fs37En33 Wo28), pigeonite lamellae (Fs51En37Wo12). Oxygen isotopes: (I. Franchi and R. Greenwood, OU) δ17O = 1.89, δ18O = 4.06, Δ17O = −0.22 (all ‰). Classification: Achondrite (eucrite); moderate shock, minimal weathering. Type specimen: A total of 15.4 g and one thin section are on deposit at MSP. MChin holds the main mass. | ||||||||||||||||
Data from: MB91 Table 2 Line 69: |
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Plots: | O isotopes: | ||||||||||||||||
Institutions and collections |
MSP: Museo di Scienze Planetarie, Via Galcianese 20/H, 59100 Prato, Italy, Italy; Website (institutional address; updated 22 Oct 2022) OU: Planetary and Space Sciences Department of Physical Sciences The Open University Walton Hall Milton Keynes MK7 6AA United Kingdom, United Kingdom (institutional address; updated 8 Dec 2011) MChin: Matteo Chinellato, Via Triestina, 126/A-30030 Tessera, Venezia, Italy; Website (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 91, MAPS 42, 413-466 (2007)
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Geography: |
Statistics: This is 1 of 9305 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |