header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 19 Jun 2024
Search for: Search type: Search limits: Display: Publication:
Names
Text help
Places
Classes
Years
Contains
Starts with
Exact
Sounds like
NonAntarctic
Falls  Non-NWAs
What's new
  in the last:
Limit to approved meteorite names
Search text:  
Northwest Africa 13991
Basic information Name: Northwest Africa 13991
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 13991
Observed fall: No
Year found: 2009
Country: (Northwest Africa)
Mass:help 122 g
Classification
  history:
Meteoritical Bulletin:  MB 110  (2022)  Eucrite-pmict
Recommended:  Eucrite-pmict    [explanation]

This is 1 of 414 approved meteorites classified as Eucrite-pmict.   [show all]
Search for other: Achondrites, Eucrites, and HED achondrites
Comments: Approved 29 May 2021
Writeuphelp
Writeup from MB 110:

Northwest Africa 13991 (NWA 13991)

(Northwest Africa)

Purchased: 2009 Jun

Classification: HED achondrite (Eucrite, polymict)

History: Purchased from a Moroccan mineral dealer at the mineral show in Sainte-Marie-aux-Mines, France

Petrography: (K. Metzler, IfP) Polymict achondritic breccia, consisting of eucritic lithic clasts (subophitic, gabbroic, granulitic) and mineral fragments (pyroxene, plagioclase) set in a fine-grained clastic matrix of related debris. Most pyroxenes exhibit augite exsolution lamellae. Several olivine fragments were found. Accessories are silica polymorph, chromite, troilite, and Ni-bearing metal.

Geochemistry: Mineral compositions and geochemistry: Granulitic eucrite clast: low-Ca pyroxene (host) Fs60.8±0.7Wo2.6±0.3 (Fs60.2-61.9Wo2.2-3.1); mean Fe/Mn (at.): 29.3; n=6. Ca-rich pyroxene (exsolution lamellae) Fs29.1±1.3Wo40.2±1.0 (Fs28.0-30.9Wo38.9-41.3); n=6. Plagioclase An87.8±1.0Or0.1±0.2 (An86.6-89.0Or0.0-0.5); n=8. Gabbroic eucrite clast: low-Ca pyroxene (host) Fs33.9±0.3Wo2.1±0.3 (Fs33.5-34.4Wo1.8-2.4); mean Fe/Mn (at.): 27.7; n=6. Ca-rich pyroxene (exsolution lamellae) Fs12.3±0.3Wo44.4±0.3 (Fs11.9-12.6Wo44.0-44.7); n=6. Plagioclase An92.3±0.6Or0.0±0.1 (An91.5-93.1Or0.0-0.1); n=8. Olivine fragments: Fa9.1±1.4 (Fa7.5-10.8); Fe/Mn (at.): 43.8; n=5.

Classification: Polymict eucrite

Data from:
  MB110
  Table 0
  Line 0:
Place of purchase:Sainte-Marie-aux-Mines, France
Date:P 2009 Jun
Mass (g):122
Pieces:1
Class:Eucrite-pmict
Shock stage:M-S2
Weathering grade:low
Fayalite (mol%):9.1±1.4
Ferrosilite (mol%):33.9-60.8; 12.3-29.1
Wollastonite (mol%):2.1-2.6; 44.4-40.2
Classifier:K. Metzler, IfP
Type spec mass (g):20
Type spec location:IfP
Main mass:anonymous
Comments:Submitted by K. Metzler (IfP)
Institutions
   and collections
IfP: Institut für Planetologie, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany (institutional address; updated 23 Jan 2012)
Catalogs:
References: Published in Gattacceca J., McCubbin F.M., Grossman J., Bouvier A., Chabot N.L., D'Orazio M., Goodrich C., Greshake A., Gross J., Komatsu M., Miao B., and Schrader D. (2022) The Meteoritical Bulletin, No. 110. Meteorit. Planet. Sci. 1-4
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Public domain photographs:
Knut Metzler            
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 9776 approved meteorites from (Northwest Africa) (plus 1862 unapproved names)

Direct link to this page