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Northwest Africa 7821
Basic information Name: Northwest Africa 7821
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7821
Observed fall: No
Year found: 2013
Country: (Northwest Africa)
Mass:help 38 g
Classification
  history:
Meteoritical Bulletin:  MB 102  (2013)  C2-ung
Recommended:  C2-ung    [explanation]

This is 1 of 25 approved meteorites classified as C2-ung.   [show all]
Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 2), and Ungrouped chondrites
Comments: Approved 18 Nov 2013
Writeuphelp
Writeup from MB 102:

Northwest Africa 7821 (NWA 7821)

(Northwest Africa)

Purchased: 2013 Feb

Classification: Carbonaceous chondrite (C2, ungrouped)

History: Purchased by GHupé in February 2013 from a dealer at the Tucson Gem and Mineral Show.

Petrography: (A. Irving and S. Kuehner, UWS) Very soft, fine grained specimen consisting of sparse tiny (0.1-0.4 mm), granular chondrules, mineral fragments and rimmed, amoeboid CAI in a brown, fine-grained matrix with possible cronstedtite and tochilinite. Some chondrules exhibit replacement by phyllosilicates. Anhydrous minerals include olivine, orthopyroxene, clinopyroxene, minor fresh kamacite and pentlandite.

Geochemistry: Olivine (Fa0.7-41.9), orthopyroxene (Fs0.6-32.3Wo3.7-2.8), clinopyroxene (Fs0.5Wo33.0). Oxygen isotopes (D. Rumble, CIW): analyses of acid-washed subsamples gave, respectively δ17O -2.98, -3.37; δ18O 0.95, 0.38; Δ17O -3.483, -3.574 per mil.

Classification: Carbonaceous chondrite (CM2-an). Oxygen isotopes do not plot with the values for other CM chondrites, but on an extension of that trend towards more 16O-rich compositions, making this specimen anomalous.

Specimens: 7.6 g and one polished thin section are at UWB. The remainder is held by GHupé.

Data from:
  MB102
  Table 0
  Line 0:
Place of purchase:Tucson
Date:P 2013 Feb
Mass (g):38
Pieces:8
Class:C2-ung
Shock stage:S2
Weathering grade:W2
Fayalite (mol%):0.7-41.9 (n=3)
Ferrosilite (mol%):0.6-32.3
Wollastonite (mol%):3.7-2.8
Classifier:A. Irving and S. Kuehner, UWS
Type spec mass (g):7.6
Type spec location:UWB
Main mass:G. Hupe
Comments:GH-453; submitted by A. Irving
Plots: O isotopes:  
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)
CIW: Carnegie Insitution Washington, Geophysical Laboratory, 5251 Broad Branch Rd., NW, Washington DC 20015, United States (institutional address)
GHupé: Gregory M. Hupé, 9003 Placid Lakes Blvd., Lake Placid, FL 33852, United States; Website (private address)
Hupe: (old address—now see GHupé or AHupé) G. and A. Hupe, 2616 Lake Youngs Court SE, Renton, WA 98058., 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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