MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 20 Jun 2022
Search for: Search type: Search limits: Display: Publication:
Text help
Starts with
Sounds like
Falls  Non-NWAs
What's new
  in the last:
Include past classifications in search
Limit to approved meteorite names
Search text:  
Northwest Africa 14146
Basic information Name: Northwest Africa 14146
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 14146
Observed fall: No
Year found: 2020
Country: (Northwest Africa)
Mass:help 399 g
Recommended:  Eucrite-mmict-an    [explanation]

This is the only approved meteorite classified as Eucrite-mmict-an.
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 31 Aug 2021
Writeup from MB 110:

Northwest Africa 14146 (NWA 14146)

(Northwest Africa)

Purchased: 2020 Dec

Classification: Eucrite-mmict-an

History: Purchased by Shun-Chung Yang and Juan Chen in December 2020 from dealer in Tindouf, Algeria.

Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Fresh monomict breccia composed of ophitic-textured diabasic eucrite clasts (mean grainsize ~1 mm) plus related crystalline debris. The major phases are unexsolved pigeonite (compositionally-zoned to ferroan subcalcic augite rims) and calcic plagioclase accompanied by accessory augite, fayalite, silica polymorph and ilmenite. One ferropigeonite grain with exsolution lamellae of subcalcic augite was observed in the studied thin section.

Geochemistry: Pigeonite cores (Fs33.4-38.2Wo6.1-7.8, FeO/MnO = 26-28, N = 3), subcalcic augite rims (Fs53.0-68.2Wo21.9-22.7, FeO/MnO = 32-34, N = 3), augite (Fs29.0Wo45.1, FeO/MnO = 34), ferropigeonite host (Fs70.2Wo7.5, FeO/MnO = 36), subcalcic augite exsolution lamella (Fs46.4Wo25.2, FeO/MnO = 31), fayalite (Fa85.4-86.2, FeO/MnO = 42-43, N = 2), plagioclase (An88.7-92.9Or0.4-0.2, N = 4).

Classification: Eucrite (monomict diabasic breccia, anomalous). Despite being a breccia, this specimen shares many attributes with unbrecciated eucrite NWA 7035, especially the notable rarity of exsolution in the strongly-zoned clinopyroxenes coupled with the prominent presence of accessory fayalite. Such pyroxene zoning (reminiscent of that observed in shergottites) is very rare in eucrites and thus is an anomalous feature.

Specimens: 28.6 g including one polished thin section at UWB; remainder with Mr. S.-C. Yang and Mr. J. Chen.

Data from:
  Table 0
  Line 0:
Place of purchase:Tindouf
Date:P 2020 Dec
Mass (g):399
Shock stage:low
Weathering grade:low
Fayalite (mol%):85.4-86.2
Ferrosilite (mol%):33.4-38.2; 46.4-68.2; 70.2; 29.0
Wollastonite (mol%):6.1-7.8; 21.9-25.2; 7.5; 45.1
Classifier:A. Irving, UWS, and P. Carpenter, WUSL
Type spec mass (g):28.6
Type spec location:UWB
Main mass:S.-C. Yang/J. Chen
Comments:Work name SCY-21; submitted by A. Irving
   and collections
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012)
WUSL: Washington Univ., One Brookings Drive, St. Louis, MO 63130, United States (institutional address; updated 17 Oct 2011)
UWB: University of Washington, Box 353010 Seattle, WA 98195, United States (institutional address; updated 27 Jul 2012)
References: Published in Meteoritical Bulletin, no. 110, in preparation (2021)
Find references in NASA ADS:
Find references in Google Scholar:

     This is 1 of 8495 approved meteorites from (Northwest Africa) (plus 1899 unapproved names)

Direct link to this page