MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 23 May 2024
Search for: Search type: Search limits: Display: Publication:
Text help
Starts with
Sounds like
Falls  Non-NWAs
What's new
  in the last:
Limit to approved meteorite names
Search text:  
Northwest Africa 6686
Basic information Name: Northwest Africa 6686
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 6686
Observed fall: No
Year found: 2010
Country: (Northwest Africa)
Mass:help 62 g
Meteoritical Bulletin:  MB 100  (2012)  Howardite
Recommended:  Howardite    [explanation]

This is 1 of 452 approved meteorites classified as Howardite.   [show all]
Search for other: Achondrites, HED achondrites, and Howardites
Comments: Approved 16 Dec 2011
Writeup from MB 100:

Northwest Africa 6686 (NWA 6686)

(Northwest Africa)

Purchased: 2010

Classification: HED achondrite (Howardite)

History: Found by an anonymous person in Western Sahara and purchased 2010 in Erfoud by G.Tomelleri.

Physical characteristics: The main mass weighs 62 g has no fusion crust.

Petrography: (V. Moggi Cecchi, G. Pratesi, S. Caporali MSP): A polymict breccia consisting of diogenitic and eucritic clasts. Diogenitic clasts are composed mainly of orthopyroxene (92% by volume), with minor olivine (5%), and plagioclase (3%). Eucritic clasts are dominated by clinopyroxene, with minor orthopyroxene displaying very fine (1-2 μm width) exsolution lamellae and anorthitic plagioclase. Minor phases include ilmenite and chromite.

Geochemistry: Diogenitic clasts show low-Ca pyroxene (Fs19-43En79-53Wo1-3) and olivine (Fa31-34); eucritic clasts show calcic plagioclase (An88-91), pigeonite (Fs51-47En37-36Wo12-17); exsolution lamellae in low-Ca pyroxene Fs51-33En40-29Wo9-38. Oxygen isotopes: (I. Franchi, R. Greenwood, OU) δ17O = 1.58, δ18O = 3.48, Δ17O = -0.24 per mil.

Classification: Achondrite (howardite) with high degree of shock and low degree of weathering.

Specimens: 12.5 g and one thin section are on deposit at MSP (MSP 5152).

Data from:
  Table 1
  Line 1482:
Place of purchase:Erfoud
Date:P 2010
Mass (g):62
Fayalite (mol%):30.1 (31-34)
Ferrosilite (mol%):24.9 (19-43)
Wollastonite (mol%):1-3
Classifier:V. Moggi Cecchi, G. Pratesi, S. Caporali, MSP
Type spec mass (g):12.5
Type spec location:MSP
Main mass:Unknown
Comments:Submitted by Vanni Moggi Cecchi
Plots: O isotopes:  
   and collections
MSP: Museo di Scienze Planetarie, Via Galcianese 20/H, 59100 Prato, Italy, Italy; Website (institutional address; updated 22 Oct 2022)
OU: Planetary and Space Sciences Department of Physical Sciences The Open University Walton Hall Milton Keynes MK7 6AA United Kingdom, United Kingdom (institutional address; updated 8 Dec 2011)
References: Published in Meteoritical Bulletin, no. 100, MAPS 49, E1-E101 (2014)
Find references in NASA ADS:
Find references in Google Scholar:
Photos uploaded by members of the Encyclopedia of Meteorites.
    (Caution, these are of unknown reliability)
Antonello Petriccione   

     This is 1 of 9746 approved meteorites from (Northwest Africa) (plus 1866 unapproved names)

Direct link to this page