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Northwest Africa 7445
Basic information Name: Northwest Africa 7445
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 7445
Observed fall: No
Year found: 2004
Country: (Northwest Africa)
Mass:help 129.4 g
Classification
  history:
Recommended:  Ureilite    [explanation]

This is 1 of 495 approved meteorites classified as Ureilite.   [show all]
Search for other: Achondrites, Ureilites
Comments: Approved 15 May 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 7445 (NWA 7445)

(Northwest Africa)

Purchased: 2004

Classification: Ureilite

History: Purchased by D. Gregory in Tuscon, Arizona. Type specimen is catalogued at ROM as M52947.

Physical characteristics: (S. Korchinos UTorG, ROM) The total mass of the sample is 129.41 g, with the main piece having mass of 128.47 g. The main mass has a weathered fusion crust with pervasive fractures. The surface is mostly covered with rust.

Petrography: (S. Korchinos UTorG, ROM). The sample exhibits typical ureilite texture with closely packed, coarse-grained silicates meeting at triple junctions. Olivine grains exhibit minor planar fracturing, undulatory extinction, and minor reduction rims. Low-Ca pyroxene exhibits twinning and undulatory extinction. Modal abundances: major olivine approximately 70%, low-Ca pyroxene 25%, and carbon 5%. Raman analysis confirms both diamond and graphite phases, though diamond is more prevalent.

Geochemistry: Mineral compositions and geochemistry: EPMA quantitative WDS (S.Korchinos, UToRG, ROM): Olivine cores have Fa24.0±1.3 (N = 17), CaO = 0.36±0.02 wt%, Cr2O3 = 0.75±0.07 wt%, and MnO = 0.40±0.02 wt%. Pyroxene cores: Fs21.0±0.3Wo6.6±0.1 (N = 10), CaO = 3.34±0.04 wt%, Cr2O3 = 1.08±0.05 wt%, MnO = 0.39±0.02 wt%.

Classification: Achondrite (ureilite). Low shock, moderate weathering.

Specimens: The main mass, thinly-sliced fragment, and thin section are held at the ROM.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Tuscon, Arizona
Date:P 2004
Mass (g):129.41
Pieces:1
Class:Ureilite
Shock stage:low
Weathering grade:moderate
Fayalite (mol%):24.0±1.3 (n=17)
Ferrosilite (mol%):21.0±0.3 (n=10)
Wollastonite (mol%):6.6±0.1 (n=10)
Classifier:S. Korchinos, UTorG, ROM
Type spec mass (g):20
Type spec location:ROM
Main mass:Gregory
Comments:Submitted by V. Di Cecco (ROM)
Institutions
   and collections
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011)
Gregory: David Gregory, 230 First Avenue, Suite 108, St. Thomas, Ontario N5R 4P5, Canada (private address)
UTorG: University of Toronto, Dept. Geology, Earth Sciences Centre, 22 Russell Street Toronto, Ontario, M5S 3B1, Canada (institutional address; updated 31 Jan 2011)
Catalogs:
References: Published in Meteoritical Bulletin, no. 108, in preparation (2019)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 6730 approved meteorites from (Northwest Africa) (plus 2025 unapproved names)

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