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Northwest Africa 12978
Basic information Name: Northwest Africa 12978
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12978
Observed fall: No
Year found: 2018
Country: Northwest Africa
Mass:help 1022 g
Classification
  history:
Recommended:  Eucrite-melt breccia    [explanation]

This is 1 of 27 approved meteorites classified as Eucrite-melt breccia.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 23 Dec 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12978 (NWA 12978)

Northwest Africa

Purchased: 2018

Classification: Eucrite melt breccia

History: Thierry Simard purchased the 1022 g sample in Rissani, Morocco, in 2018 November.

Physical characteristics: Sample is rounded-irregular in shape, coated with a dark-brown weathered patina containing numerous pits that show the surface expression of lithic fragments. The cut face shows a brecciated structure composed of light-colored igneous-textured clasts set in a finer-grained dark matrix.

Petrography: Description and classification: (A. Love, App): Sample is a melt rock-supported breccia composed of 1.2 mm - 2.5 cm rounded-irregular-shaped brecciated, rare cumulate and basaltic-textured clasts and related mineral debris set in within a quenched melt matrix. Basaltic clasts have subophitic textures and contain exsolved pyroxenes. Additional minerals are: fayalite, a silica polymorph, ilmenite, rare zircon and phosphate.

Geochemistry: (A. Love, App): Low Ca pyroxene (Fs61.9±2.0Wo2.9±1.7, Fe/Mn=31.2±1.3, Mg#36.2±2.0, n=14); high Ca pyroxene (Fs28.5±2.4Wo42.6±0.8, Fe/Mn=30.9±0.9, n=8); plagioclase (An89.2±6.2Or0.5±0.6, n=10).

Classification: HED Achondrite (eucrite melt breccia). Textures and mineral compositions (Fe/Mn ratios and Mg# of pyroxenes) indicate this sample is a basaltic eucrite melt breccia.

Specimens: Thierry Simard holds the main mass. Several fragments and a polished thin section comprise 22 g type specimen which is on deposit at App.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Rissani
Date:P 2018
Mass (g):1022
Pieces:1
Class:Eucrite melt breccia
Shock stage:low
Weathering grade:W1
Ferrosilite (mol%):61.9±2.0; 28.5±2.4
Wollastonite (mol%):2.9±1.7; 42.6±0.8
Magnetic suscept.:2.92
Classifier:A. Love, App
Type spec mass (g):22
Type spec location:App
Main mass:Thierry Simard
Finder:Unknown
Comments:Submitted by Anthony Love
Institutions
   and collections
App: Department of Geology, 572 Rivers St., Appalachian State University, Boone, NC 28608, United States (institutional address; updated 7 Mar 2013)
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 6 approved meteorites from Northwest Africa (plus 3 unapproved names)

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