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Northwest Africa 4901
Basic information Name: Northwest Africa 4901
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 4901
Observed fall: No
Year found: 2007
Country: (Northwest Africa)
Mass:help 24 g
Meteoritical Bulletin:  MB 97  (2010)  Achondrite (ungrouped)
Recommended:  Achondrite-ung    [explanation]

This is 1 of 138 approved meteorites classified as Achondrite-ung.   [show all]
Search for other: Achondrites, Ungrouped achondrites
Comments: Approved 10 Dec 2009
Writeup from MB 97:

Northwest Africa 4901

Purchased 2007 in Erfoud, Morocco

Achondrite (ungrouped basalt)

History: The meteorite was found by an anonymous finder in northwest Africa and bought by the main mass holder in Erfoud, Morocco.

Physical characteristics: One brownish 24 g fragment was found.

Petrography: (A. Greshake, MNB): The meteorite displays an unbrecciated texture dominated by coarsegrained pyroxene and small, recrystallized plagioclase. Pyroxene is Ca-rich and shows abundant exsolution lamellae. Minor phases include silica, Ca-phosphates, ilmenite, and Ti-rich chromite.

Geochemistry: Mineral composition (EPMA): plagioclase, An79–87; pyroxene, Fs34.4–62.5Wo6.5–39.7; the Fe⁄Mn ratio of pyroxene is approximately 70.

Classification: Achondrite (ungrouped basalt); low degree of shock, low degree of weathering; pairing of the meteorite with NWA 011, 2400, 2976, 4587, and others in this pairing group seems likely.

Specimens: A total of 4.9 g plus one polished thin section are on deposit at MNB. Ralew holds the main mass.

Data from:
  Table 1
  Line 187:
Place of purchase:Erfoud
Mass (g):24
Class:Achondrite (ungrouped)
Shock stage:Low
Weathering grade:Low
Fayalite (mol%):34.4-62.5
Ferrosilite (mol%):6.5-39.7
Classifier:A. Greshake, MNB
Type spec mass (g):4.9
Type spec location:MNB
Main mass:Ralew
Comments:Pairing of the meteorite with NWA 011, 2400, 2976, 4587 seems likely. See written description
   and collections
MNB: Museum für Naturkunde, Invalidenstraße 43, D-10115 Berlin, Germany (institutional address; updated 24 Dec 2011)
Ralew: Stefan Ralew, Kunibertstraße 29, 12524 Berlin, Germany; Website (private address)
References: Published in Meteoritical Bulletin, no. 97, MAPS 45, 449-493 (2010)
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     This is 1 of 9368 approved meteorites from (Northwest Africa) (plus 1875 unapproved names)

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