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Northwest Africa 11785
Basic information Name: Northwest Africa 11785
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 11785
Observed fall: No
Year found: 2015
Country: (Northwest Africa)
Mass:help 822 g
Classification
  history:
Recommended:  Eucrite-melt breccia    [explanation]

This is 1 of 26 approved meteorites classified as Eucrite-melt breccia.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 26 May 2018
Writeuphelp
Writeup from MB 107:

Northwest Africa 11785 (NWA 11785)

(Northwest Africa)

Purchased: 22 May 2015

Classification: HED achondrite (Eucrite, melt breccia)

History: Purchased by Jay Piatek from a Moroccan meteorite dealer.

Physical characteristics: Single stone, no fusion crust. Exterior shows numerous white clasts set in a dark matrix of shock melt.

Petrography: (C. Agee, UNM) Microprobe examination shows a cataclastic mix of fragmental pyroxene and feldspar grains engulfed in abundant shock melt veins and pools. Accessory chromite and ilmenite were detected.

Geochemistry: (C. Agee, UNM) Low-Ca pyroxene Fs53.1Wo1.9, Fe/Mn=32, n=1; high-Ca pyroxene Fs22.6Wo44.1, Fe/Mn=28, n=1; plagioclase An90.5±1.3, n=2; Shock melt (20 μm defocused electron beam, proxy for bulk meteorite composition): SiO2=46.1±1.9, TiO2=0.8±0.02, Al2O3=25.1±9.9, Cr2O3=0.13±0.10, MgO=5.0±3.5, FeO=9.2±6.0, MnO=0.28±0.19, CaO=14.4±2.7, Na2O=0.66±0.27, K2O=0.05±0.01 (all wt%), n=5.

Classification: Eucrite-melt breccia, eucrite pyroxene compositions are consistent with cumulate eucrite.

Specimens: 20 g including a probe mount on deposit at UNM, Jay Piatek holds the main mass.

Data from:
  MB107
  Table 0
  Line 0:
Place of purchase:Morocco
Date:P 22 May 2015
Mass (g):822
Pieces:1
Class:Eucrite-melt breccia
Shock stage:high
Weathering grade:moderate
Ferrosilite (mol%):53.1, 22.6
Wollastonite (mol%):1.9, 44.1
Classifier:C. Agee, UNM
Type spec mass (g):20
Type spec location:UNM
Main mass:Jay Piatek
Comments:Field name JP-75; submitted by C. Agee, UNM
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)
Catalogs:
References: Published in Meteoritical Bulletin, no. 107, in preparation (2018)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7035 approved meteorites from (Northwest Africa) (plus 2000 unapproved names)

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