header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 27 Nov 2021
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 13856
Basic information Name: Northwest Africa 13856
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 13856
Observed fall: No
Year found: 2020
Country: Algeria
Mass:help 374 g
Classification
  history:
Recommended:  Achondrite-ung    [explanation]

This is 1 of 108 approved meteorites classified as Achondrite-ung.   [show all]
Search for other: Achondrites, Ungrouped achondrites
Comments: Approved 6 May 2021
Writeuphelp
Writeup from MB 110:

Northwest Africa 13856 (NWA 13856)

Algeria

Purchased: 2020

Classification: Achondrite (ungrouped)

History: Fabien Kuntz purchased the 374.3 g sample from a meteorite prospector in Tindouf, Algeria, in 2020.

Physical characteristics: Sample has an irregular shape and a dark-brown exterior. The cut face shows a crystalline interior crosscut by black veins.

Petrography: Description and classification (A. Love, App) Sample shows poikilitic texture composed of (vol%): 1.5mm (n=12) orthorhombic pyroxene oikocrysts (30), anhedral-subhedral olivine (49) occurring as 76 µm (n=11) chadacrysts and 230 µm (n=23) phenocrysts and interstitial plagioclase (13). Lath-shaped pyroxenes share a preferred orientation and some are mantled with Ca-rich pyroxene. Vugs and vesicles occur within plagioclase. Chondrules are absent. Additional minerals are: albitic plagioclase with acicular inclusions of pyroxene, rare troilite, Ti-chromite, apatite, FeOH. Sample vestiges or relict chondritic-textured lithologies; evidence of rapid growth textures (cellular metal-sulfide mixtures, or spherical metal droplets).

Geochemistry: Olivine (Fa23.9±0.3, Fe/Mn=45.6±0.7, n=10); low-Ca Pyroxene (Fs20.0±0.8Wo3.9±1.5, Fe/Mn=28.2±0.7, n=12); high-Ca pyroxene (Fs13.1±0.7Wo33.5±2.2, Fe/Mn=22.1±0.6, n=5); plagioclase (Ab85.9±2.2Or3.5±0.6, n=6). Oxygen Isotopes: (Karen Ziegler, UNM) analyses of acid-washed subsamples by laser fluorination gave (all per mill): δ17O=3.536, 3.786, 3.682; δ18O=4.647, 5.172, 4.947; Δ17O=1.082, 1.055, 1.070.

Classification: Achondrite (ungrouped) strong shock, moderate weathering. Sample shows cumulate igneous texture, pyroxenes with compositional zoning and has mineralogic and isotopic similarities to L ordinary chondrites.

Specimens: Fabien Kuntz holds the main mass. An endcut weighing 32.12g and a polished thin section are on deposit at App.

Data from:
  MB110
  Table 0
  Line 0:
Place of purchase:Tindouf
Date:P 2020
Mass (g):374
Pieces:1
Class:Achondrite (ungrouped)
Shock stage:strong
Weathering grade:moderate
Fayalite (mol%):23.9±0.3
Ferrosilite (mol%):20.0±0.8; 13.1±0.7
Wollastonite (mol%):3.9±1.5; 33.5±2.2
Magnetic suscept.:4.01
Classifier:A. Love, App
Type spec mass (g):32.12
Type spec location:App
Main mass:Fabien Kuntz
Comments:Submitted by Anthony Love
Plots: O isotopes:  
Institutions
   and collections
UNM: Institute of Meteoritics MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 USA, United States; Website (institutional address; updated 12 Feb 2015)
App: Department of Geology, 572 Rivers St., Appalachian State University, Boone, NC 28608, United States (institutional address; updated 7 Mar 2013)
Kuntz: Fabien Kuntz, France; Website (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 110, in preparation (2021)
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Public domain photographs:
Anthony Love      
Geography:

Algeria
Coordinates:Unknown.

Statistics:
     This is 1 of 1153 approved meteorites from Algeria (plus 27 unapproved names) (plus 4 impact craters)

Direct link to this page