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Northwest Africa 8729
Basic information Name: Northwest Africa 8729
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 8729
Observed fall: No
Year found: 2014
Country: (Northwest Africa)
Mass:help 108.4 g
Classification
  history:
Meteoritical Bulletin:  MB 104  (2015)  Eucrite-mmict
Recommended:  Eucrite-mmict    [explanation]

This is 1 of 230 approved meteorites classified as Eucrite-mmict.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 4 Feb 2015
Writeuphelp
Writeup from MB 104:

Northwest Africa 8729 (NWA 8729)

(Northwest Africa)

Found: 2014

Classification: HED achondrite (Eucrite, monomict)

History: Recovered in April 2014 near the borders of Mauritania, Western Sahara and Algeria. Purchased in Mauritania in June 2014.

Physical characteristics: A single stone with irregular exterior. A saw cut reveals white feldspar grains up to 3 mm, green-brown pyroxene grains, all set in a fine-grained light-gray groundmass.

Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows approximately equal amounts of pyroxene and plagioclase, slightly brecciated, numerous shock fractures. Accessory troilite, chromite, ilmenite, and silica.

Geochemistry: (C. Agee and N. Muttik, UNM). Low-Ca pyroxene Fs55.4±1.5Wo2.1±1.4, Fe/Mn=32±1, n=15; augite Fs24.3±1.4Wo41.8±1.9, Fe/Mn=30±2, n=17; plagioclase An86.2±4.0Ab13.1±3.7Or0.7±0.3, n=5.

Classification: Achondrite (eucrite). Equilibrated, clear separation of high-Ca and low-Ca pyroxene, no pigeonite present. Moderate weathering grade, high shock stage.

Specimens: 20.7 g including a probe mount on deposit at UNM, DPitt holds the main mass.

Data from:
  MB104
  Table 0
  Line 0:
Place of purchase:Mauritania
Date:2014
Mass (g):108.4
Pieces:1
Class:Eucrite-mmict
Shock stage:high
Weathering grade:moderate
Ferrosilite (mol%):55.4±1.5
Wollastonite (mol%):2.1±1.4
Classifier:C. Agee, UNM
Type spec mass (g):20.7
Type spec location:UNM
Main mass:Darryl Pitt
Comments:Field name MAC 81; submitted by C. Agee, UNM
Institutions
   and collections
UNM: Institute of Meteoritics MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 USA, United States; Website (institutional address; updated 12 Feb 2015)
DPitt: Darryl Pitt, 225 West 83rd Street, New York, NY 10024, United States; Website (private address)
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:
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Geography: 
Coordinates:Unknown.

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

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