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Northwest Africa 7255
Basic information Name: Northwest Africa 7255
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7255
Observed fall: No
Year found: 2004
Country: Morocco
Mass:help 607 g
Classification
  history:
Meteoritical Bulletin:  MB 100  (2012)  CO3.5
Recommended:  CO3.5    [explanation]

This is 1 of 12 approved meteorites classified as CO3.5.   [show all]
Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 3), CM-CO clan chondrites, and CO chondrites
Comments: Approved 18 May 2012
Writeuphelp
Writeup from MB 100:

Northwest Africa 7255 (NWA 7255)

Morocco

Purchased: 2004

Classification: Carbonaceous chondrite (CO3.5)

History: Purchased by Blaine Reed in Denver, 2004.

Physical characteristics: One stone, saw cut reveals numerous small chondrules set in dark-brown matrix.

Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows a variety of small chondrules (typically 50-300 microns) set in fine-grained weathered matrix.

Geochemistry: (C. Agee and N. Wilson, UNM) Type I chondrules Fa6.6±3.9 range 0.7-14.5, Fe/Mn=66±39, Cr2O3 0.02-0.71 wt%, n=14, Type II chondrules Fa32.9±8.4 range 18.5-47.9, Fe/Mn=112±29, Cr2O3 0.03-0.23 wt%, n=19. Low-Ca pyroxene mean Fs4.0 range 0.8-18.6 and Wo1.5±1.2, n=24.

Classification: Carbonaceous chondrite (CO3.5), subtype based mean values and distribution of Fa compositions, similar to Lancé (Scott and Jones, 1990), weathering grade W3.

Specimens: 21.9 g including a probe mount on deposit at UNM, Reed holds the main mass.

Data from:
  MB100
  Table 1
  Line 1698:
Place of purchase:Denver
Date:P 2004
Mass (g):607
Pieces:1
Class:CO3.5
Weathering grade:W3
Fayalite (mol%):6.6±3.9 (0.7-14.5); 32.9±8.4 (18.5-47.9)
Ferrosilite (mol%):4.0 (0.8-18.6)
Wollastonite (mol%):1.5±1.2
Classifier:C. Agee, UNM
Type spec mass (g):21.9
Type spec location:UNM
Main mass:Reed
Comments:Submitted by C. Agee
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)
Reed: Blaine Reed, P.O. Box 1141, Delta, CO 81416, United States; Website (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 100, MAPS 49, E1-E101 (2014)
Find references in NASA ADS:
Find references in Google Scholar:
Geography:

Morocco
Coordinates:Unknown.

Statistics:
     This is 1 of 1991 approved meteorites from Morocco (plus 31 unapproved names) (plus 1 impact crater)

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