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Northwest Africa 7908
Basic information Name: Northwest Africa 7908
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7908
Observed fall: No
Year found: 2004
Country: (Northwest Africa)
Mass:help 157 g
Classification
  history:
Meteoritical Bulletin:  MB 102  (2013)  Diogenite
Recommended:  Diogenite    [explanation]

This is 1 of 511 approved meteorites classified as Diogenite.   [show all]
Search for other: Achondrites, Diogenites, and HED achondrites
Comments: Approved 27 Jul 2013
Writeuphelp
Writeup from MB 102:

Northwest Africa 7908 (NWA 7908)

(Northwest Africa)

Purchased: Feb 2004

Classification: HED achondrite (Diogenite)

History: A pre-cut specimen was purchased from a Moroccan trader by Edwin Thompson, and a portion was donated to Cascadia, in February, 2004.

Physical characteristics: A cut slab shows grey clasts ranging from <1 mm to 1.5 cm set in a light-brown matrix. Black clasts are also present. Rust halos surround sparse metal grains in the matrix. The surface of the sample is rough, light brown to grey to black, and mostly lacks fusion crust.

Petrography: (A. Ruzicka, Cascadia) In thin section the meteorite consists almost entirely of low-Ca pyroxene and chromite. Coarse-grained (1-2 mm) orthopyroxenite (gray) and chromite (black) clasts are set in a matrix of smaller pyroxene and chromite clasts. Grains are highly fractured and pyroxene shows undulose to mosaic extinction. One metal grain is partly replaced by weathering product.

Geochemistry: Phase compositions are highly equilibrated: low-Ca pyroxene Wo1.6±0.1 Fs25.1±0.8 Fe/Mn =26.5±2.7 (N=37), chromite Cr/(Cr=Al) = 0.83± 0.01 Fe/(Fe+Mg)= 0.78± 0.02 (N=14) (atomic units).

Classification: Achondrite (diogenite). Textures and mineralogy suggest a monomict orthopyroxenitic breccia. Minor weathering.

Specimens: 27.0 g, one polished thin section, and one butt are on deposit at CascadiaThompson holds the main mass.

Data from:
  MB102
  Table 0
  Line 0:
Place of purchase:Tucson, Arizona, USA
Date:P Feb 2004
Mass (g):157
Pieces:1
Class:Diogenite
Shock stage:moderate
Weathering grade:minor
Ferrosilite (mol%):25.1±0.8
Wollastonite (mol%):1.6±0.1
Classifier:A. Ruzicka, Cascadia
Type spec mass (g):27
Type spec location:Cascadia
Main mass:Thompson
Comments:Lab number CML0150.; submitted by A. Ruzicka
Institutions
   and collections
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011)
Thompson: Edwin Thompson, 5150 Dawn St., Lake Oswego, OR 97035, United States (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 102, MAPS 50, 1662, September 2015
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 9111 approved meteorites from (Northwest Africa) (plus 1873 unapproved names)

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