header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 10 Jul 2019
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 4425
Basic information Name: Northwest Africa 4425
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 4425
Observed fall: No
Year found: 2006
Country: Algeria
Mass:help 579 g
Classification
  history:
Meteoritical Bulletin:  MB 93  (2008)  CK3
Recommended:  CK3    [explanation]

This is 1 of 37 approved meteorites classified as CK3.   [show all]
Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 3), CK chondrites, CK3 chondrites, and CV-CK clan chondrites
Comments: Approved 17 Apr 2008
Revised 4 Aug 2008: final writeup
Writeuphelp
Writeup from MB 93:

Northwest Africa 4425

Algeria

Find: May 2006

Carbonaceous chondrite (CK3)

History: A stone was purchased by P. Thomas in May 2006.

Physical characteristics: A complete, ventifacted stone weighing 579 g, without fusion crust. It has a brownish color indicating significant terrestrial alteration.

Petrography: (M. Bourot-Denise, MNHN) Chondrules are mm-sized. Most CAIs are also visible to the naked eye. The type specimen contains a CAI 1.5 cm in diameter rimmed with spinel and diopside. Chondrules are generally porphyritic with wide rims, and contain magnetite beads. Large opaque nodules of magnetite and sulfide are present in the matrix. Matrix is either crystallized or fine, with abundant small magnetite crystals. BSE images indicate that this chondrite is not completely equilibrated; olivines and pyroxene in porphyritic chondrules are zoned. In the type specimen, there is an angular clast, 2 cm in diameter, containing small, porphyritic pyroxene chondrules (100- 500 µm); chondrules and well-crystallized matrix are completely equilibrated; magnetite is finely scattered through the clast and does not make up nodules as in the host; the interface between the clast and the host is highlighted by small, euhedral magnetites.

Geochemistry: Olivine (Fa13.6±12.6; range Fa0.54-34.1), low-Ca pyroxene (Fs16.8±11.0; range Fs2.8-30.7), magnetite (Cr2O3 = 2.6-3.7, MgO = 0.87-1.15 [both wt%]) all in the CK3 domain. Pyroxene in the angular clast: Fs23.35±0.86. Magnetic susceptibility (J. Gattacceca, CEREGE) log χ = 4.6 10-9 m3/kg.

Classification: Carbonaceous chondrite (CK3, estimated subtype 3.8); minimal shock and moderate weathering.

Type specimens: A total of 32.8 g of sample (1 sawn fragment) and two polished mounts are on deposit at MNHN. Thomas holds the main mass.

Submitted by: M. Bourot-Denise, MNHN.

Data from:
  MB93
  Table 2
  Line 46:
Place of purchase:Algeria
Date:2006
Class:CK3
Institutions
   and collections
CEREGE: CEREGE BP 80 Avenue Philibert, Technopole de l'Arbois 13545 Aix-en-Provence Cedex 4 France, France (institutional address; updated 29 Oct 2018)
MNHN: Museum National d'Histoire Naturelle, IMPMC-CP52, 57 rue Cuvier, 75005 Paris, France, France; Website (institutional address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 93, MAPS 43, 571-632 (2008)
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Photos from the Encyclopedia of Meteorites:
Don Edwards   
Photos uploaded by members of the Encyclopedia of Meteorites.
    (Caution, these are of unknown reliability)
Mirko Graul         
Geography:

Algeria
Coordinates:Unknown.

Statistics:
     This is 1 of 964 approved meteorites from Algeria (plus 26 unapproved names) (plus 4 impact craters)

Direct link to this page