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Northwest Africa 7721
Basic information Name: Northwest Africa 7721
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7721
Observed fall: No
Year found: 2012
Country: (Northwest Africa)
Mass:help 32 g
Classification
  history:
Meteoritical Bulletin:  MB 102  (2013)  Martian (shergottite)
Recommended:  Martian (shergottite)    [explanation]

This is 1 of 189 approved meteorites (plus 1 unapproved name) classified as Martian (shergottite).   [show all]
Search for other: Martian meteorites
Comments: Approved 6 May 2013
Writeuphelp
Writeup from MB 102:

Northwest Africa 7721 (NWA 7721)

(Northwest Africa)

Purchased: 2012 Dec

Classification: Martian meteorite (Shergottite)

History: Purchased in Temara, Morocco in 2012 December by Adam Aaronson.

Physical characteristics: A single stone (32 g) composed of brown, pale green and vesicular white grains.

Petrography: (A. Irving and S. Kuehner, UWS) Relatively coarse grained with both poikilitic and equigranular domains; some oikocrysts are up to 4 mm across. Composed of olivine, orthopyroxene, clinopyroxene (pigeonite and subcalcic augite), intermediate plagioclase (vesicular), Ti-rich chromite, ilmenite (with baddeleyite inclusions), pyrrhotite and rare merrillite. Melt inclusions in olivine (composed of glass+Al-bearing clinopyroxene+minor merrillite) are surrounded by radial expansion cracks.

Geochemistry: Olivine (Fa29.1-33.6; FeO/MnO = 45-53), orthopyroxene (Fs21.2-21.6Wo3.1; FeO/MnO = 31), pigeonite (Fs22.3-28.8Wo6.9-8.2; FeO/MnO = 27-31).

Classification: Martian (shergottite, poikilitic). On the basis of texture, mineral compositions and find location, this specimen appears to be paired with the two stones classified as NWA 1950.

Specimens: 6.6 g of material is on deposit at UWBAaronson holds the main mass.

Data from:
  MB102
  Table 0
  Line 0:
Place of purchase:Temara
Date:P 2012 Dec
Mass (g):32
Pieces:1
Class:Martian (shergottite)
Shock stage:high
Weathering grade:low
Fayalite (mol%):29.1-33.6
Ferrosilite (mol%):21.2-21.6; 22.3-28.8
Wollastonite (mol%):3.1; 6.9-8.2
Classifier:A. Irving and S. Kuehner, UWS
Type spec mass (g):6.6
Type spec location:UWB
Main mass:A. Aaronson
Comments: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. 102, MAPS 50, 1662, September 2015
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6781 approved meteorites from (Northwest Africa) (plus 2047 unapproved names)

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