header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 18 May 2022
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 14598
Basic information Name: Northwest Africa 14598
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 14598
Observed fall: No
Year found: 2006
Country: Morocco
Mass:help 15 kg
Classification
  history:
Recommended:  H3    [explanation]

This is 1 of 661 approved meteorites (plus 2 unapproved names) classified as H3.   [show all]
Search for other: H chondrites, H chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3)
Comments: Approved 15 Jan 2022
Writeuphelp
Writeup from MB 111:

Northwest Africa 14598 (NWA 14598)

Morocco

Purchased: 2006

Classification: Ordinary chondrite (H3)

History: The 15 kg meteorite was purchased in Morocco in 2006 by S. Gabis, who provided the type specimen masses to UWO for classification. Contact with the owner has since been lost.

Physical characteristics: The 15 kg individual has longest dimension >46 cm, and has an extensive fusion crust modified by a well-developed desert polish and iron oxide weathering. Physical properties: The 28.71 g type specimen also shows weathering and provides a grain density via He pycnometry of 3.427±0.005 g/cm3 and a magnetic susceptibility of log χ (× 10-9 m3/kg) = 4.72.

Petrography: (M. Bramble, P. McCausland, UWO) Transmitted light microscopy reveals a pervasive deep red matrix coloration and penetrating oxide veining through the majority of both the matrix and chondrules. Using reflected light microscopy, metal averaged 10.5±2.4 %, and apparent weathering product oxides was 42 % by area, using ImageJ analysis. Polished thin sections display abundant chondrules with sizes up to 2.1 mm in diameter. Nearly all chondrules appear disrupted or broken save for a few smaller (0.10-0.20 mm) radiating, micro- and cryptocrystalline chondrules. Olivine shows undulatory extinction. Micro-XRD examination of olivine grains revealed minor streaking of diffrection spots, consistent with low to moderate shock.

Geochemistry: Mineral compositions and Geochemistry: (M. Bramble, R. Flemming UWO) EPMA: olivine Fa18.9±0.5 (n=9); Ca-poor pyroxene Fs 13.5±5.5 (n=14). Unit cell variation of olivine grains was measured with micro-XRD for both olivine chondrules and matrix olivine. Targeting three olivine chondrules, a 300 µm beam observed: a at 4.7752 Å (0.0039), b at 10.2728 Å (0.0061), and c at 6.0116 Å (0.0027). Five matrix olivine grains targeted with a 100 µm beam observed: a = 4.7729 Å (0.0073), b = 10.2661 Å (0.0083), c = 6.0082 Å (0.0073).

Classification: Ordinary chondrite: H3 (S2) W2. Matrix black opaque patches in thin section suggest a petrographic grade of less than 4 as recrystallization of the matrix is neither extensive nor complete. PMD of olivine compositions also suggests petrographic grade 3.9. In situ micro-XRD targeted locations on the type specimen and revealed abundant weathering phases. Dolomite, goethite, magnetite, and hematite were identified at specimen weathering spots. Micro-XRD of polished thin section spots matched goethite and dolomite in almost all of the targeted locations. No altered silicates were identified via micro-XRD and no clay minerals were detected despite specific attempts made to detect them.

Specimens: Two type specimen masses (30 g each), two polished thin sections, and an assortment of smaller masses (13 pieces ranging from 11.5 g to 0.1 g) are located at UWO. The 15 kg main mass location is unknown and is presumed to be with the owner.

Data from:
  MB111
  Table 0
  Line 0:
Place of purchase:Morocco
Date:P 2006
Mass (g):15000
Pieces:1
Class:H3
Shock stage:S2
Weathering grade:W2
Fayalite (mol%):18.9 ± 0.5 (n=9)
Ferrosilite (mol%):13.5 ± 5.5 (n=14)
Magnetic suscept.:4.72
Classifier:M. Bramble, P. McCausland, R. Flemming, UWO
Type spec mass (g):28.75
Type spec location:UWO
Main mass:Unknown
Finder:anonymous
Comments:Submitted by P. McCausland
Institutions
   and collections
UWO: University of Western Ontario, Department of Earth Sciences, BGS 1026, 1151 Richmond St. N, London, Ontario, Canada N6A 5B7, Canada (institutional address; updated 18 Jul 2015)
Catalogs:
References: Published in Meteoritical Bulletin, no. 111, in preparation (2022)
Find references in NASA ADS:
Find references in Google Scholar:
Geography:

Morocco
Coordinates:Unknown.

Statistics:
     This is 1 of 1837 approved meteorites from Morocco (plus 24 unapproved names) (plus 1 impact crater)

Direct link to this page