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Northwest Africa 12342
Basic information Name: Northwest Africa 12342
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12342
Observed fall: No
Year found: 2018
Country: (Northwest Africa)
Mass:help 526 g
Classification
  history:
Recommended:  Eucrite-melt breccia    [explanation]

This is 1 of 25 approved meteorites classified as Eucrite-melt breccia.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 14 Dec 2018
Writeuphelp
Writeup from MB 107:

Northwest Africa 12342 (NWA 12342)

(Northwest Africa)

Purchased: 2018 Aug

Classification: HED achondrite (Eucrite, melt breccia)

Petrography: (K. Metzler, IfP) Subrounded eucritic lithic clasts (up to 2 cm) with ophitic to subophitic textures and mineral fragments (pyroxene, plagioclase, silica polymorph) embedded in a vesicular crystallized melt. The modal amount of melt is 30-50 vol%. The latter shows a fan-spherulitic texture consisting of skeletal pyroxene and plagioclase crystals with sizes up to 100 µm. Vesicles can reach sizes of ~400 µm. Many lithic clasts are surrounded by a thin dark layer of a more fine-grained crystallized melt. Most pyroxene fragments show shock-deformed exsolution lamellae. Accessories are silica polymorph, ilmenite, Cr-spinel, and troilite.

Geochemistry: Mineral compositions and geochemistry: Lithic clasts: Low-Ca pyroxene Fs59.8±2.0Wo3.5±1.4 (Fs56.1-62.8Wo1.8-6.2); mean Fe/Mn (at.): 33; n=14. Ca-pyroxene Fs26.7±0.4 Wo43.2±0.4 (Fs25.9-27.3Wo42.7-44.1; n=12). Plagioclase An88.9±1.1Or0.4±0.3 (An87.9-90.6Or0-0.8); n=8.

Data from:
  MB107
  Table 0
  Line 0:
Place of purchase:Guelmim, Morocco
Date:P 2018 Aug
Mass (g):526
Pieces:8
Class:Eucrite-melt breccia
Shock stage:moderate
Weathering grade:low
Ferrosilite (mol%):59.8; 26.7
Wollastonite (mol%):3.5; 43.2
Classifier:K. Metzler, IfP
Type spec mass (g):20
Type spec location:IfP, Münster
Main mass:Nourddine Azelmat, Morocco
Comments:Submitted by K. Metzler, IfP
Institutions
   and collections
IfP: Institut für Planetologie, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany (institutional address; updated 23 Jan 2012)
Catalogs:
References: Published in Meteoritical Bulletin, no. 107, in preparation (2018)
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Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6900 approved meteorites from (Northwest Africa) (plus 2035 unapproved names)

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