header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 17 Oct 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 13968
Basic information Name: Northwest Africa 13968
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 13968
Observed fall: No
Year found: 2019
Country: (Northwest Africa)
Mass:help 89 g
Classification
  history:
Recommended:  R3    [explanation]

This is 1 of 45 approved meteorites classified as R3.   [show all]
Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3)
Comments: Approved 17 Jul 2021
Writeuphelp
Writeup from MB 110:

Northwest Africa 13968 (NWA 13968)

(Northwest Africa)

Purchased: 2019

Classification: Rumuruti chondrite (R3)

History: Acquired by Mark Lyon at 2019 Tucson Gem and Mineral Show in Tucson, AZ

Physical characteristics: (L. Garvie, ASU) Dark, shiny, sandblasted stone lacking fusion crust. Chondrules visible over the surface of the stone and on the cut surface. A 2 × 3 cm cut surface is dark showing an abundance of light-colored chondrules, largest to 1.5 mm, and abundant Fe-Ni sulfides. Cut surface shows two prominent 1-cm breccia clasts. Clasts are noticeable by their darker and more abundant matrix compared with the bulk of the stone. Very little weathering visible in the stone.

Petrography: (A. Herbst and W. Cortez, ASU) Approximately ~30% chondrules, 55 vol% matrix, 10 vol% subhedral to euhedral olivine grains, 5% sulfides, and <1 vol% Al-rich chondrules and CAIs. Sulfides occur as micron and submicron sized grains dispersed in the matrix, nodules to 700 µm, and as mantles around chondrules. Two prominent breccia clasts were observed, ~8 mm and ~5 mm in size. Chondrules as 0.4 ± 0.2 mm (n=74), though one to 1.5 mm. Chondrules are dominantly porphyritic olivine-pyroxene, but also show barred olivine and radial pyroxene textures. EPMA results show a rare diopside-rimmed CAI (~0.1 mm in size) composed of spinel and ilmenite inclusions identified within the larger breccia clast. The matrix within the two clasts is fine-grained while the matrix outside of the clasts is coarser-grained. The bulk matrix hosts lithic fragments of pyroxene and subhedral to anhedral olivine grains as well as compositionally zoned olivine. Phosphates (merrillite and Cl-apatite-rich) aggregates along with one euhedral spinel are also identified within the matrix of the bulk meteorite. Platinum-group bearing metal-rich inclusions are located within metal sulfide hosts, including a ~5 µm gold and platinum grain embedded in a pentlandite host, a ~600 nm osmium-rich grain embedded in a troilite host, and a ~3 µm iridium-arsenide grain in a pentlandite host.

Geochemistry: (A. Herbst and W. Cortez, A. Wittmann, ASU) Olivine Fa26.9±14.0, range 0.6-48.3 (n=57); low-Ca pyroxene En83.5±9.0Fs15.1±8.6Wo1.4±2.1 (n=30); high-Ca pyroxene En45.5±5.5Fs11.8±2.8Wo42.7±8.2 (n=4).

Classification: Petrography (texture and average chondrule size) and geochemistry consistent with an R3 chondrite.

Data from:
  MB110
  Table 0
  Line 0:
Place of purchase:Tucson
Date:P 2019
Mass (g):89
Pieces:1
Class:R3
Shock stage:low
Weathering grade:low
Fayalite (mol%):26.9±14.0 (n=57)
Ferrosilite (mol%):15.1±8.6
Wollastonite (mol%):1.4±2.1 (n=30)
Classifier:A. Herbst, W. Cortez, L. Garvie, A. Wittman, ASU
Type spec mass (g):23
Type spec location:ASU
Main mass:Mark Lyon
Comments:ASU#2148; submitted by L. Garvie
Institutions
   and collections
ASU: Center for Meteorite Studies, Arizona State University, Tempe, Arizona 85287-1404, United States; Website (institutional address; updated 14 Jan 2012)
Catalogs:
References: Published in Meteoritical Bulletin, no. 110, in preparation (2021)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7937 approved meteorites from (Northwest Africa) (plus 1960 unapproved names)

Direct link to this page