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Northwest Africa 12431
Basic information Name: Northwest Africa 12431
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12431
Observed fall: No
Year found: 2016
Country: (Northwest Africa)
Mass:help 87.5 g
Classification
  history:
Recommended:  LL3    [explanation]

This is 1 of 313 approved meteorites classified as LL3.   [show all]
Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3)
Comments: Approved 16 Feb 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12431 (NWA 12431)

(Northwest Africa)

Purchased: 12 Dec 2016

Classification: Ordinary chondrite (LL3)

Physical characteristics: Exterior surfaces of the type specimen are bumpy and covered with patches of brown-colored remnant fusion crust and light tan caliche. Interior surfaces are bluish-gray, with well-defined chondrules and abundant sulfide with some metal. One cut face shows a 6x3.5mm dark clast.

Petrography: (M. Hutson, A. Ruzicka, Cascadia) In thin section, the sample contains chondrules with a variety of sizes and textures, including some that are rimmed by sulfide. Along the edge of the section is a roughly triangular shaped clast (base approximately 4.9 mm × height approximately 4.9 mm), with a spinifex texture, consisting of acicular olivine set in a feldspathic matrix.

Geochemistry: Mineral compositions and geochemistry: (M. Hutson, R. Kostynick, A. Ruzicka, Cascadia) Host olivine (Fa26.4±4.1, N=29, Fa coefficient of variation = 15.6); low-Ca pyroxene (Fs16.2±7.2Wo0.7±0.5, N=31).

Classification: LL3. Estimated subtype 3.8.

Specimens: Cascadia holds 17.7 g in three pieces, in addition to a polished thin section.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Ebay
Date:P 12 Dec 2016
Mass (g):87.5
Pieces:1
Class:LL3
Weathering grade:W1
Fayalite (mol%):26.4±4.1
Ferrosilite (mol%):16.2±7.2
Wollastonite (mol%):0.7±0.5
Classifier:M. Hutson, R. Kostynick, A. Ruzicka, Cascadia
Type spec mass (g):17.7
Type spec location:Cascadia
Main mass:Bastien Baecker, Huntsville
Comments:Lab number CML 0940; submitted by Alex Ruzicka
Institutions
   and collections
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011)
Catalogs:
References: Published in Meteoritical Bulletin, no. 108, in preparation (2019)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6730 approved meteorites from (Northwest Africa) (plus 2025 unapproved names)

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