header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 11 Oct 2019
Search for: Search type: Search limits: Display: Publication:
Names
Text help
Places
Classes
Years
Contains
Starts with
Exact
Sounds like
NonAntarctic
Falls  Non-NWAs
What's new
  in the last:
Limit to approved meteorite names
Search text:  
Northwest Africa 12867
Basic information Name: Northwest Africa 12867
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12867
Observed fall: No
Year found: 2011
Country: Morocco
Mass:help 19.3 g
Classification
  history:
Recommended:  Eucrite    [explanation]

This is 1 of 441 approved meteorites (plus 1 unapproved name) classified as Eucrite.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 11 Oct 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12867 (NWA 12867)

Morocco

Purchased: Febuary 2011

Classification: HED achondrite (Eucrite)

History: Sample number (LM57450) in the ROM collection.

Physical characteristics: A single small and rounded stone covered with a black shiny fusion crust. The cut stone shows a fresh grey surface.

Petrography: The thin section shows one distinct lithological clast (60 mm in diameter) and a mixture of mineral and basaltic clasts embedded within a fine-grained clastic matrix. The lithological clast is a medium-grained enstatite-plagioclase rock of granular texture with a large chromite situated within. Both high-Ca exsolved augite and pigeonite is present as mineral clasts; both show little to no mosaicism. Plagioclase is relatively fresh both within the lithological clast and as mineral clasts with no maskelynite present. Minor minerals are olivine, ilmenite, chromite, tridymite, quartz, apatite, merrillite, zircon and FeNi metal.

Geochemistry: Mineral compositions and geochemistry: Enstatite (Wo1.7-4.9En50.9-57.5Fs40.7-46.6;FeO/MnO=29-35.4), pigeonite (Wo5.1-17.1En32.2-37.8Fs45-59.4; FeO/MnO=27.5-32) with augite lamellae (Wo36.2-37.7 En26.9-34.5Fs29.1-44.9; FeO/MnO=27.8-32.6), Ferrosilite (Wo2.4-3.6En40.2-43.7Fs52.6-57.1; FeO/MnO=29.7-31.7) with high-Ca pyroxene (Wo19-20En35.9-39.5Fs40.4-44.9; FeO/MnO=28.1-29.2). Plagioclase ranges from An59-97 with an average of An87. Olivine ranges from Fo40.2-71.9 with an average of Fo64.4.

Classification: Eucrite (polymict breccia)

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Tuson Gem and Mineral Show
Date:P Febuary 2011
Mass (g):19.25
Pieces:1
Class:Eucrite
Shock stage:low
Weathering grade:low
Fayalite (mol%):31.4±10.6 (N = 10)
Ferrosilite (mol%):35±11.1 (N=3); 47.8±13.4 (N=25)
Wollastonite (mol%):31.3±19.3 (N=3); 5.5±10.5 (N=25)
Classifier:B. Rider-Stokes, UPort
Type spec mass (g):5.84
Type spec location:ROM
Main mass:ROM
Comments:Submitted by V. Di Cecco (ROM)
Institutions
   and collections
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011)
UPort: University of Portsmouth Winston Churchill Avenue Portsmouth, Hampshire PO1 2UP, United Kingdom (institutional address; updated 11 Oct 2019)
Catalogs:
References: Published in Meteoritical Bulletin, no. 108, in preparation (2019)
Find references in NASA ADS:
Find references in Google Scholar:
Geography:

Morocco
Coordinates:Unknown.

Statistics:
     This is 1 of 1402 approved meteorites from Morocco (plus 16 unapproved names) (plus 1 impact crater)

Direct link to this page