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Northwest Africa 12825
Basic information Name: Northwest Africa 12825
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12825
Observed fall: No
Year found: 2019
Country: (Northwest Africa)
Mass:help 20 g
Classification
  history:
Recommended:  Diogenite-pm    [explanation]

This is 1 of 39 approved meteorites classified as Diogenite-pm.   [show all]
Search for other: Achondrites, Diogenites, and HED achondrites
Comments: Approved 21 Sep 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12825 (NWA 12825)

(Northwest Africa)

Purchased: 2019

Classification: HED achondrite (Diogenite, polymict)

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

Physical characteristics: Many dark brownish fragments with some fusion crust.

Petrography: The meteorite is a fragmental breccia composed of a large diversity of mostly angular mineral fragments and some impact melt clasts set into a fine-grained clastic matrix. Minerals include diogenitic orthopyroxene of two different compositions, Fe-rich eucritic low-Ca pyroxene with augite exsolution lamellae, two compositionally different types of olivine, and calcic plagioclase. Minor phases are silica, chromite, FeS, and barite. No metallic Fe was detected. Contains some calcite-filled veins due to terrestrial alteration.

Geochemistry: diogenetic pyroxene: Fs24.4±0.2Wo2.5±0.1 (Fs24.1-24.8Wo2.3-2.6, FeO/MnO=31-35, n=11); diogenetic pyroxene: Fs20.7±0.2Wo1.1±0.1 (Fs20.4-21.2Wo1.0-1.1, FeO/MnO=30-35, n=11); eucritic low-Ca pyroxene host crystals to augite lamellae: Fs63.3±0.6Wo2.0±0.2 (Fs62.3-64.0Wo1.8-2.2, FeO/MnO=35-37, n=11); augite exsolution lamellae: Fs28.7±0.3Wo41.5±0.6 (Fs28.2-29.2Wo40.7-42.5, FeO/MnO=30-37, n=12); olivine: Fa22.6±0.2 (Fa22.3-22.8, FeO/MnO=48±2, n=10); olivine: Fa12.7±0.3 (Fa12.3-13.0, FeO/MnO=43±4, n=10); calcic plagioclase: An91.8±1.0 (An89.8-93.6, n=14)

Classification: Diogenite due to high abundance of orthopyroxene and presence of olivine.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Morocco
Date:P 2019
Mass (g):20
Pieces:1
Class:Diogenite-pm
Shock stage:moderate
Weathering grade:moderate
Fayalite (mol%):22.6; 12.7
Ferrosilite (mol%):24.4; 20.7; 63.3; 28.7
Wollastonite (mol%):2.5; 1.1; 2.0; 41.5
Classifier:A. Greshake, MNB
Type spec mass (g):4
Type spec location:MNB
Main mass:Said Yousfi
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. 108, in preparation (2019)
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Public domain photographs:
Ansgar Greshake      
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7035 approved meteorites from (Northwest Africa) (plus 2000 unapproved names)

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