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Northwest Africa 12430
Basic information Name: Northwest Africa 12430
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12430
Observed fall: No
Year found: 2006
Country: (Northwest Africa)
Mass:help 485 g
Classification
  history:
Recommended:  LL4-6    [explanation]

This is 1 of 69 approved meteorites classified as LL4-6.   [show all]
Search for other: LL chondrites, LL chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7)
Comments: Approved 23 Jan 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12430 (NWA 12430)

(Northwest Africa)

Purchased: Sept 2006

Classification: Ordinary chondrite (LL4-6)

History: Found in northwest Africa, donated to Cascadia July 2012.

Physical characteristics: In cut slices, exterior is black with brown patches, interior is gray with well-defined chondrules and dark- and light-colored angular clasts.

Petrography: (M. Hutson, A. Ruzicka, Cascadia) Thin section shows a host lithology composed of a mix of well-defined chondrules and chondrule fragments. Both plagioclase feldspar (less than 40 μm across) and feldspathic glass are present. The host lithology surrounds a dozen angular coarser-grained chondritic clasts, the largest of which (Clast 5) is approximately 4 × 5 mm in size. Clast 5 and Clast 4 (approximately 2 × 4 mm in size) were analyzed. Clast 5 is coarse-grained, with plagioclase feldspar grains up to 110 μm in length, and contains three barely discernable chondrules. Clast 4 contains two chondrules with indistinct edges and plagioclase feldspar grains between 40 and 60 μm in length.

Geochemistry: Mineral compositions and geochemistry: (M. Hutson and J. Graham-Davis, Cascadia) Olivine (host Fa31.9±0.5, N=22; Clast 4 Fa32.0±0.7, N=10; Clast 5 Fa32.2±0.2, N=7), low-Ca pyroxene (host Fs19.2±5.2Wo1.1±0.1, N=15; Clast 4 Fs26.0±0.5Wo2.0±0.2, N=7; Fs26.2±0.6Wo2.0±0.3, N=5), plagioclase feldspar (Clast 4 Ab85.1±0.9Or3.3±0.7, N=6; Clast 5 Ab85.2±1.2Or3.7±0.3, N=3).

Classification: LL4-6 genomict breccia, based on iron contents in olivine and pyroxene and plagioclase feldspar grain size.

Specimens: Cascadia holds 22.6 g in two pieces, in addition to a polished thin section and a mounted butt.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Denver
Date:P Sept 2006
Mass (g):485.1
Pieces:1
Class:LL4-6
Weathering grade:W1
Fayalite (mol%):31.9±0.5
Ferrosilite (mol%):19.2±5.2
Wollastonite (mol%):1.1±0.8
Classifier:M. Hutson, J. Graham-Davis, A. Ruzicka, Cascadia
Type spec mass (g):22.6
Type spec location:Cascadia
Main mass:Mr. Ronnie McKenzie, Pretoria, South Africa
Comments:Specimen numbers RM-6 and CML0679; 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 7385 approved meteorites from (Northwest Africa) (plus 1955 unapproved names)

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