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Northwest Africa 4921
Basic information Name: Northwest Africa 4921
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 4921
Observed fall: No
Year found: 2007
Country: (Northwest Africa)
Mass:help 3.7 g
Classification
  history:
Recommended:  H7    [explanation]

This is 1 of 29 approved meteorites classified as H7.   [show all]
Search for other: H chondrites, H chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7)
Comments: Approved 26 Mar 2022
Writeuphelp
Writeup from MB 111:

Northwest Africa 4921 (NWA 4921)

(Northwest Africa)

Purchased: 2007

Classification: Ordinary chondrite (H7)

History: The meteorite was purchased from a local meteorite dealer in Erfoud, Morocco.

Physical characteristics: Dark brownish fragment without fusion crust.

Petrography: The meteorite shows a recrystallized texture with abundant triple junctions between adjoining minerals. Low-Ca pyroxene and feldspar often poikilitically enclose rounded olivine grains. Grain sizes vary from 30 to 100 µm. Minor phases include FeNi metal, troilite, chromite, and merrillite. Grain boundaries are often decorated by iron oxides. No relict chondrules detected.

Geochemistry: olivine: Fa17.7±0.1 (Fa17.6-18.0, FeO/MnO=45±4, n=10); low-Ca pyroxene: Fs16.0±0.2Wo3.2±0.6 (Fs15.7-16.2Wo1.7-3.7, FeO/MnO=28±2, n=10); Ca-pyroxene: Fs8.1±0.6Wo39.6±2.0 (Fs7.2-8.8Wo37.6-42.6, FeO/MnO=18±2, n=7); feldspar: An13.8±2.1Ab82.0±1.7Or4.2±0.6, n=10

Data from:
  MB111
  Table 0
  Line 0:
Place of purchase:Erfoud, Morocco
Date:P 2007
Mass (g):3.7
Pieces:1
Class:H7
Shock stage:S1
Weathering grade:W3
Fayalite (mol%):17.7
Ferrosilite (mol%):16.0; 8.1
Wollastonite (mol%):3.2; 39.6
Classifier:A. Greshake, MNB
Type spec mass (g):0.8
Type spec location:MNB
Main mass:Hanno Strufe
Comments:Submitted by Ansgar Greshake
Institutions
   and collections
MNB: Museum für Naturkunde, Invalidenstraße 43, D-10115 Berlin, Germany (institutional address; updated 24 Dec 2011)
Catalogs:
References: Published in Meteoritical Bulletin, no. 111, in preparation (2022)
Find references in NASA ADS:
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Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 8495 approved meteorites from (Northwest Africa) (plus 1899 unapproved names)

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