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Northwest Africa 6112
Basic information Name: Northwest Africa 6112
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 6112
Observed fall: No
Year found: 2000
Country: (Northwest Africa)
Mass:help 1040 g
Classification
  history:
Meteoritical Bulletin:  MB 104  (2015)  Achondrite-ung
Recommended:  Achondrite-ung    [explanation]

This is 1 of 84 approved meteorites classified as Achondrite-ung.   [show all]
Search for other: Achondrites, Ungrouped achondrites
Comments: Approved 24 Aug 2015
Writeuphelp
Writeup from MB 104:

Northwest Africa 6112 (NWA 6112)

(Northwest Africa)

Purchased: 2000

Classification: Ungrouped achondrite

Physical characteristics: A 1040 g stone, partially covered by fusion crust.

Petrography: The section shows a granular texture composed of elongate to rounded olivine grains (0.3-0.5 mm, ~90 vol%) and minor anhedral plagioclase (~0.2-0.5 mm) and augite (~1-2 mm). Large augite grains (~1-2 mm) poikilitically enclose rounded olivine grains. Fine-grained (partly-weathered) FeNi-FeS and orthopyroxene occur along grain boundaries of the silicate minerals.

Geochemistry: Olivine (Fa25-28, FeO/MnO~53), Pyroxenes: Augite (n = 12), Fs10.9±0.3En46.2±0.3Wo42.9±0.4 (Fs10.2-11.2En45.8-46.4Wo42.1-43.6) and Low-Ca pyroxene, Fs22.6En76.6Wo0.8 (n = 2), and plagioclase (Or2-3An20-21).

Classification: The coarse-grained granular texture indicates that this meteorite is not a chondritic meteorite, but an achondrite or primitive achondrite. The composition of olivine (Fa25-29) is similar to L chondrites. However, the scarcity of orthopyroxene indicates that this meteorite is not related to ordinary chondrites. The mode of olivine (~90 vol%) and the presence of minor augite indicate that this meteorite is petrologically similar to brachinite group. However, the Fa composition of olivine is slightly outside the range of brachinite group (Fa30-35) and similar to those of an ungrouped achondrite, Divnoe (Fa20-28). On the basis of the petrologic data presented above, this meteorite is classified as an ungrouped achondrite.

Specimens: 38 g type specimen at NIPR.

Data from:
  MB104
  Table 0
  Line 0:
Place of purchase:Alnif, Morocco
Date:P 2000
Mass (g):1040
Pieces:1
Class:Achondrite-ung
Shock stage:low
Weathering grade:low
Fayalite (mol%):26.1±0.7 (n=70)
Ferrosilite (mol%):10.9±0.3 (n=12)
Classifier:A. Yamaguchi, NIPR
Type spec mass (g):38
Type spec location:NIPR
Main mass:Bruno and Carine Fectay
Comments:Submitted by A. Yamaguchi
Institutions
   and collections
NIPR: Antarctic Meteorite Research Center, National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan; Website (institutional address; updated 9 Dec 2013)
Fectay: Bruno Fectay and Carine Bidaut, La Memoire de la Terre SARL, 39800 Aumont, France; Website (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
Find references in NASA ADS:
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Photos:
CreditPhotos
Photos uploaded by members of the Encyclopedia of Meteorites.
    (Caution, these are of unknown reliability)
Christophe PICQ   
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6877 approved meteorites from (Northwest Africa) (plus 2037 unapproved names)

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