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Northwest Africa 4285
Basic information Name: Northwest Africa 4285
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 4285
Observed fall: No
Year found: 2005
Country: (Northwest Africa)
Mass:help 48 g
Classification
  history:
Meteoritical Bulletin:  MB 91  (2007)  Diogenite
Recommended:  Diogenite    [explanation]

This is 1 of 465 approved meteorites classified as Diogenite.   [show all]
Search for other: Achondrites, Diogenites, and HED achondrites
Comments: Approved 28 Mar 2007
Writeuphelp
Writeup from MB 91:

Northwest Africa 4285

Algeria

Find: 2005

Achondrite (diogenite)

History and physical characteristics: A 48 g buff-colored stone with fresh, black fusion crust was purchased in Erfoud, Morocco, in December 2005.

Petrography: (J. Wittke and T. Bunch, NAU ) Coarse-grained breccia of fragments up to 1.8 cm with interstitial cataclastite. Mineral modes in vol% are: orthopyroxene = 88, olivine = 5, chromite = 3, plagioclase = 2, and FeS + metal = 2.

Mineral composition and geochemistry: Orthopyroxene (Fs24.5Wo3.7; FeO/MnO = 26); olivine (Fa29.1; FeO/MnO = 54), plagioclase (An88), chromite (Cr/(Cr+Al) = 0.68), troilite (Cr = 2.2 wt%), and metal (Ni = 1.15 wt%).

Classification: Achondrite (diogenite, olivine, and plagioclase-bearing); S3, minimal weathering.

Type specimen: A total of 10 g and one thin section are on deposit at NAU. Thompson is the main mass holder.

Data from:
  MB91
  Table 2
  Line 277:
Place of purchase:Erfoud, Morocco
Date:2005
Mass (g):48
Pieces:1
Class:Dio
Shock stage:S3
Weathering grade:minimal
Ferrosilite (mol%):24.5
Classifier:T. Bunch and J. Wittke, NAU
Type spec mass (g):10
Type spec location:NAU
Main mass:Thompson
Institutions
   and collections
NAU: Geology, Bldg 12 Knoles Dr Northern Arizona University, Flagstaff, AZ 86011, United States; Website (institutional address; updated 12 Apr 2012)
Thompson: Edwin Thompson, 5150 Dawn St., Lake Oswego, OR 97035, United States (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 91, MAPS 42, 413-466 (2007)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7885 approved meteorites from (Northwest Africa) (plus 1958 unapproved names)

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