header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 26 Feb 2024
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 15431
Basic information Name: Northwest Africa 15431
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 15431
Observed fall: No
Year found: 2020
Country: (Northwest Africa)
Mass:help 35 g
Classification
  history:
Meteoritical Bulletin:  MB 111  (2023)  Lunar (frag. breccia)
Recommended:  Lunar (frag. breccia)    [explanation]

This is 1 of 30 approved meteorites classified as Lunar (frag. breccia).   [show all]
Search for other: Lunar meteorites
Comments: Approved 19 Nov 2022
Writeuphelp
Writeup from MB 111:

Northwest Africa 15431 (NWA 15431)

(Northwest Africa)

Purchased: Mar 2020

Classification: Lunar meteorite (frag. breccia)

History: Meteorite was purchased by Mr. Jasper Spencer from a Moroccan dealer (Nor Eddine Azelmat) in March 2020 via e-mail. Mr. Spencer sent a 7.9 g end piece to Cascadia for classification.

Physical characteristics: Physical Characteristics: The exterior of the sample is covered with a desert varnish; no evidence of a fusion crust was visible on the end piece received by Cascadia. The cut face shows sub-angular to sub-rounded clasts in a variety of colors, including white, cream, light brown, reddish-brown to black, set in a dark brownish-gray matrix.

Petrography: (M. Hutson and A. Ruzicka, Cascadia): Sample is a breccia comprised of large (up to 3 mm in length) sub-angular to sub-rounded lithic clasts set in a matrix of finer (< 250 µm) angular clastic material. The larger clasts contain abundant glass, while the matrix contains crystalline anorthitic feldspar. Accessory phases include ilmenite, silica polymorph, armalcolite, troilite, FeNi-metal, and Ca-phosphate grains observed in x-ray maps but too small to analyze.

Geochemistry: (M. Hutson and A. Ruzicka, Cascadia): Plagioclase feldspar: Ab4.2±2.0Or0.6±0.4An95.2±2.1, N=33; Glass (in large clasts): Ab4.5±5.6Or1.2±1.4An94.3±6.0, N=21; Olivine: Fa40.1±8.9, Fe/Mn=87.2±5.0, N=9; Low-Ca pyroxene: Fs23.5±8.4Wo3.6±0.6, Fe/Mn=55.0±8.6, N=21; Pigeonite: Fs24.8±7.7Wo10.0±3.9, N=13; Augite: Fs21.8±20.6Wo40.7±9.0, N=19.

Classification: Lunar (frag. breccia). This meteorite is best described as a lunar feldspathic fragmental breccia based on texture and chemistry.

Specimens: Cascadia holds 6.9 g in two pieces, as well as a polished thin section and material in an epoxy butt; Mr. Jasper Spencer holds the main mass.

Data from:
  MB111
  Table 0
  Line 0:
Place of purchase:e-mail
Date:P Mar 2020
Mass (g):35
Pieces:1
Class:Lunar (frag. breccia)
Fayalite (mol%):40.1±8.9 (N=9)
Ferrosilite (mol%):23.5±8.4 (N=21)
Wollastonite (mol%):3.6±0.6 (N=21)
Classifier:M. Hutson and A. Ruzicka, Cascadia
Type spec mass (g):7.9
Type spec location:Cascadia
Main mass:Mr. Jasper Spencer
Comments:Lab number CML 1437; submitted by Melinda Hutson
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 Gattacceca J., McCubbin F. M., Grossman J. N., Schrader D. L., Chabot N. L., D’Orazio M., Goodrich C., Greshake A., Gross J., Joy K. H., Komatsu M. and Miao B. (2023) The Meteoritical Bulletin, No. 111. Meteoritics & Planetary Science 58, 901–904. ?
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 9570 approved meteorites from (Northwest Africa) (plus 1871 unapproved names)

Direct link to this page