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| Northwest Africa 4423 | |||||||||||||
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| Basic information | Name: Northwest Africa 4423 This is an OFFICIAL meteorite name. Abbreviation: NWA 4423 Observed fall: No Year found: 2006 Country: Morocco Mass:  91.9 g | ||||||||||||
| Classification history: |
This is 1 of 79 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 6 Mar 2008 Revised 4 Aug 2008: final writeup | ||||||||||||
| Writeup |
Writeup from MB 93:
Northwest Africa 4423 Morocco Find: May 2006 Carbonaceous chondrite (CK3) History: A stone, said to have been found near Hammada du Guir, Morocco, was purchased by P. Thomas in May 2006. Physical characteristics: One stone, weighing 91.94 g, entirely covered with a very black fusion crust. Petrography: (M. Bourot-Denise, MNHN) Chondrules and CAIs are clearly visible to the naked eye and are mm-sized; CAIs are particularly abundant. Magnetite, the most abundant opaque mineral, makes large nodules around chondrules or, in association with sulfides (mostly pyrrhotite), in the matrix; it is also found as smaller grains rimming chondrules, AOAs and CAIs, and in chondrule rims; very small flecks of magnetite are located in a few areas of finer matrix. In BSE images, the chondrite appears not to be completely equilibrated, with zoned olivines and low-Ca pyroxenes in POP chondrules. Outside chondrules, high-Ca pyroxene is augite and diopside. The studied polished section features a large CAI, 3000 µm in size, rimmed with small magnetites. Geochemistry: Olivine (mean Fa = 16.4 ± 12.7, range 0.31- 32.7), low-Ca pyroxene (Fs = 7.9 ± 8.6, range 1.1-24.1; magnetite (Cr2O3 = 2.35, MgO = 0.84 [both in wt%]), plagioclase (An22.6-77.6). Magnetic susceptibility: (J. Gattacceca, CEREGE) = log χ = 4.7 10-9 m3/kg. Classification: Carbonaceous chondrite (CK3; estimated subtype 3.8); minimal shock and moderate weathering. Type specimens: A total of 19.1 g of sample (4 sawn fragments) and one polished mount is on deposit at MNHN. Thomas holds the main mass. Submitted by: M. Bourot-Denise, MNHN. | ||||||||||||
| Data from: MB93 Table 2 Line 45: |
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| Institutions and collections |
CEREGE: CEREGE
BP 80
Avenue Philibert, Technopole de l'Arbois
13545 Aix-en-Provence Cedex 4
France, France (institutional address; updated 10 Jun 2023) MNHN: Museum National d'Histoire Naturelle, IMPMC-CP52, 57 rue Cuvier, 75005 Paris, France, France; Website (institutional address) |
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| Catalogs: |
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| References: | Published in Meteoritical Bulletin, no. 93, MAPS 43, 571-632 (2008)
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Geography:
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Statistics: This is 1 of 1974 approved meteorites from Morocco (plus 37 unapproved names) (plus 1 impact crater) | ||||||||||||