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Northwest Africa 11254
Basic information Name: Northwest Africa 11254
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 11254
Observed fall: No
Year found: 2016
Country: (Northwest Africa)
Mass:help 18 g
Classification
  history:
Recommended:  CM-an    [explanation]

This is 1 of 9 approved meteorites classified as CM-an.   [show all]
Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 2), CM chondrites, and CM-CO clan chondrites
Comments: Approved 27 Mar 2018
Writeuphelp
Writeup from MB 107:

Northwest Africa 11254 (NWA 11254)

(Northwest Africa)

Purchased: 2016 Oct

Classification: Carbonaceous chondrite (CM, anomalous)

History: Purchased by Dustin Dickens in October 2016 from a dealer in Laayoune, Morocco.

Petrography: (A. Irving and S. Kuehner, UWS ; L. Garvie, ASU) Very small chondrules (apparent diameter 200±100 µm), mineral fragments and some very fine grained CAI are set in an extremely fine grained matrix (~30 vol.%, black in thin section) containing pyrrhotite, kamacite, and taenite. No phyllosilicates were detected by X-ray diffraction.

Geochemistry: Olivine (Fa0.8-58.6, N = 3), orthopyroxene (Fs1.8-3.1Wo1.1-0.4, N = 3), clinopyroxene (Fs1.5-2.0Wo45.3-42.6, N = 2). Oxygen isotopes (Karen Ziegler, ASU) of acid-washed subsamples: δ17O 0.241, -0.423; δ18O 9.268, 8.823; Δ17O -4.653, -5.082 (all per mil).

Classification: Carbonaceous chondrite (CM-an). The anomalous character comes from the absence of phyllosilicates, and the oxygen isotopes that plot below the trend for CM chondrites.

Specimens: 3.6 g including one polished thin section at UWB; remainder with Mr. D. Dickens.

Data from:
  MB107
  Table 0
  Line 0:
Place of purchase:Laayoune
Date:P 2016 Oct
Mass (g):18
Pieces:1
Class:CM-an
Shock stage:S2
Weathering grade:low
Fayalite (mol%):0.8-58.6
Ferrosilite (mol%):1.8-3.1
Wollastonite (mol%):1.1-0.4
Classifier:A. Irving and S. Kuehner, UWS
Type spec mass (g):3.6
Type spec location:UWB
Main mass:D. Dickens
Comments:Work name DD17-6; submitted by A. Irving
Plots: O isotopes:  
Institutions
   and collections
ASU: Center for Meteorite Studies, Arizona State University, Tempe, Arizona 85287-1404, United States; Website (institutional address; updated 14 Jan 2012)
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)
Catalogs:
References: Published in Meteoritical Bulletin, no. 107, in preparation (2018)
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Public domain photographs:
A. Irving   
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6900 approved meteorites from (Northwest Africa) (plus 2027 unapproved names)

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