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Northwest Africa 8428
Basic information Name: Northwest Africa 8428
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 8428
Observed fall: No
Year found: 2014
Country: (Northwest Africa)
Mass:help 1470 g
Classification
  history:
Meteoritical Bulletin:  MB 104  (2015)  Eucrite-pmict
Recommended:  Eucrite-pmict    [explanation]

This is 1 of 344 approved meteorites classified as Eucrite-pmict.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 1 May 2015
Writeuphelp
Writeup from MB 104:

Northwest Africa 8428 (NWA 8428)

(Northwest Africa)

Purchased: 2014 Mar

Classification: HED achondrite (Eucrite, polymict)

History: Purchased in Temara, Morocco by Adam Aaronson in March 2014 and subsequently sold to Fredric Stephan.

Petrography: (A. Irving and S. Kuehner, UWS) Complex fragmental breccia composed of basaltic eucrite clasts, microgabbroic eucrite clasts, ~5 vol.% diogenitic orthopyroxene grains (of several different compositions) and sparse dark, metal-bearing, fragmental genomict breccia clasts within a matrix of finer related mineral debris. Minerals are calcic plagioclase, orthopyroxene, exsolved pigeonite, fayalite, ferropigeonite, ilmenite, troilite and kamacite (as irregularly shaped grains).

Geochemistry: Diogenitic orthopyroxene (Fs20.9Wo2.3; Fs25.0Wo1.9; Fs33.4Wo2.5; FeO/MnO = 30-32 N = 3), fayalite (Fa87.4-87.5; FeO/MnO = 40-45, N = 2), ferropigeonite (Fs58.7Wo22.5; FeO/MnO = 31). Pigeonite grains consist of exsolution lamellae of clinopyroxene (Fs24.8-25.2Wo43.0-43.7; FeO/MnO = 29-32; N = 2) within host orthopyroxene (Fs61.1-61.0Wo1.5-1.6; FeO/MnO = 33; N = 2).

Classification: Eucrite (polymict breccia).

Specimens: 21.4 g including one polished thin section at UWB. The remainder is held by Mr. F. Stephan.

Data from:
  MB104
  Table 0
  Line 0:
Place of purchase:Temara
Date:P 2014 Mar
Mass (g):1470
Pieces:1
Class:Eucrite-pmict
Shock stage:low
Weathering grade:low
Fayalite (mol%):87.4-87.5
Ferrosilite (mol%):20.9-33.4; 24.8-25.2; 61.1-61.0
Wollastonite (mol%):2.3-2.5; 43.0-43.7; 1.5-1.6
Classifier:A. Irving and S. Kuehner, UWS
Type spec mass (g):21.4
Type spec location:UWB
Main mass:F. Stephan
Comments:M1702; submitted by A. Irving
Institutions
   and collections
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012)
UWB: University of Washington, Box 353010 Seattle, WA 98195, United States (institutional address; updated 27 Jul 2012)
Aaronson: Sahara Overland Ltd., Harhora, Temara, 12000, Morocco (private address; updated 3 Jan 2010)
Catalogs:
References: Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7101 approved meteorites from (Northwest Africa) (plus 2004 unapproved names)

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