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Northwest Africa 13981
Basic information Name: Northwest Africa 13981
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 13981
Observed fall: No
Year found: 2020
Country: (Northwest Africa)
Mass:help 4.04 kg
Recommended:  Eucrite-an    [explanation]

This is 1 of 13 approved meteorites classified as Eucrite-an.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 18 Jun 2021
Writeup from MB 110:

Northwest Africa 13981 (NWA 13981)

(Northwest Africa)

Purchased: 2020 Jan

Classification: HED achondrite (Eucrite, anomalous)

History: Purchased by Ziyao Wang in January 2020 from a dealer in Laayoune, Morocco.

Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Diabasic igneous texture. Composed predominantly of prismatic grains of highly shocked exsolved pigeonite and lath-like grains of shocked plagioclase with accessory silica polymorph, ilmenite, troilite, low-Ti chromite and rare zircon. Pyroxene is shock-darkened (orange to brown in thin section) and in part polygranular; some plagioclase has been transformed to isotropic maskelynite, but some is birefringent yet exhibits highly undulose extinction. Some veinlets and pockets of shock glass (deep sepia brown to black in thin section with "swirly" texture) are also present.

Geochemistry: Low-Ca pyroxene host (Fs65.0-67.9Wo1.6-1.9, FeO/MnO = 34-36, N = 4), augite exsolution lamellae (Fs28.6-29.5Wo43.4-44.4, FeO/MnO = 33-37, N = 4), plagioclase (An74.8-77.5Or0.7-1.2, N = 3).

Classification: Eucrite (unbrecciated, anomalous, shocked, maskelynite-bearing). The pyroxenes in this specimen are much more ferroan than in typical eucrites, and have compositions akin to those in anomalous eucrites NWA 11729 and NWA 12445; the plagioclase is also more sodic than in typical eucrites.

Specimens: 30.8 g including one polished thin section at UWB; remainder held jointly by Ziyao Wang and Fangmei Wang.

Data from:
  Table 0
  Line 0:
Place of purchase:Laayoune
Date:P 2020 Jan
Mass (g):4038
Shock stage:high
Weathering grade:low
Ferrosilite (mol%):65.0-67.9;28.6-29.3
Wollastonite (mol%):1.6-1.9; 43.4-44.4
Classifier:A. Irving, UWS, and P. Carpenter, WUSL
Type spec mass (g):30.8
Type spec location:UWB
Main mass:WangZ/F. Wang
Comments:Work name WZY-18; submitted by A. Irving
   and collections
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012)
WUSL: Washington Univ., One Brookings Drive, St. Louis, MO 63130, United States (institutional address; updated 17 Oct 2011)
UWB: University of Washington, Box 353010 Seattle, WA 98195, United States (institutional address; updated 27 Jul 2012)
WangZ: Ziyao Wang, Hebei GEO University North Campus, Huai An dong road 127, Shijiazhuang, Hebei Province , China (private address; updated 25 Jun 2021)
References: Published in Meteoritical Bulletin, no. 110, in preparation (2021)
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Photos uploaded by members of the Encyclopedia of Meteorites.
    (Caution, these are of unknown reliability)
Ziyao Wang         

     This is 1 of 7937 approved meteorites from (Northwest Africa) (plus 1960 unapproved names)

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