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Northwest Africa 7646
Basic information Name: Northwest Africa 7646
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7646
Observed fall: No
Year found: 2012
Country: (Northwest Africa)
Mass:help 402 g
Classification
  history:
Meteoritical Bulletin:  MB 102  (2013)  L3
Recommended:  L3    [explanation]

This is 1 of 711 approved meteorites classified as L3.   [show all]
Search for other: L chondrites, L chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3)
Comments: Approved 27 Sep 2013
Writeuphelp
Writeup from MB 102:

Northwest Africa 7646 (NWA 7646)

(Northwest Africa)

Purchased: 2012 Dec

Classification: Ordinary chondrite (L3)

History: Purchased by Darryl Pitt in December 2012 from a dealer in Erfoud, Morocco.

Petrography: (A. Irving and S. Kuehner, UWS) Closely packed chondrules (0.2 to 2 mm) dominated by PO and PP. Minerals include olivine, orthopyroxene, subcalcic augite, augite, sodic plagioclase, chromite, troilite and altered kamacite.

Geochemistry: Olivine Fa3.9-44.1, n=10; Cr2O3 in ferroan olivine 0.03-0.11 wt.%, mean 0.07 wt.%, sd 0.03 wt.%, N = 7. Orthopyroxene Fs1.8-19.7Wo0.9-1.9; subcalcic augite Fs9.4Wo32.4; augite Fs11.6Wo41.0.

Classification: Estimated L3.5. Chondrule size and range consistent with L. Subtype estimated to be 3.5 based on Cr2O3 range in ferroan olivine. Estimation of subtype based on histograms (Fig. 4) in Grossman and Brearley (2005).

Specimens: 24.6 g and one polished thin section at UWB. DPitt holds the main mass.

Bibliography:
  • Grossman J.N. and Brearley A.J. (2005) The onset of metamorphism in ordinary and carbonaceous chondrites. Meteorit. Planet. Sci. 40, 87-122. (link)
Data from:
  MB102
  Table 0
  Line 0:
Place of purchase:Erfoud
Date:P 2012 Dec
Mass (g):402
Pieces:1
Class:L3
Shock stage:S2
Weathering grade:W2
Fayalite (mol%):3.9-44.1
Ferrosilite (mol%):1.8-19.7
Wollastonite (mol%):0.9-1.9
Classifier:A. Irving and S. Kuehner, UWS
Type spec mass (g):24.6
Type spec location:UWB
Main mass:DPitt
Comments:D724; 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)
DPitt: Darryl Pitt, 225 West 83rd Street, New York, NY 10024, United States; Website (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 7472 approved meteorites from (Northwest Africa) (plus 1988 unapproved names)

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