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| Northwest Africa 14712 | |||||||||||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 14712 This is an OFFICIAL meteorite name. Abbreviation: NWA 14712 Observed fall: No Year found: 2012 Country: Morocco Mass:  6.32 kg | ||||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 83 approved meteorites classified as LL4-6. [show all] Search for other: LL chondrites, LL chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||||||
| Comments: | Approved 21 Feb 2022 | ||||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 111:
Northwest Africa 14712 (NWA 14712) Morocco Purchased: 2012 Classification: Ordinary chondrite (LL4-6) History: Sample was purchased at the Tucson mineral show in 2012 from A. Aaronson, who acquired it from Morocco. Sample is catalogued at ROM as M59929. Physical characteristics: Large, fresh regmalypted individual with light development of desert polish. Most surfaces have dark fusion crust. Broken surfaces reveal a green-grey interior bearing dark subangular breccia clasts up to several cm in size. Matrix contains sparse, disseminated metal grains. Physical properties: Magnetic susceptibilty of a fusion crust-free 15.77 g specimen is log χ (× 10-9 m3/kg) = 3.73. Petrography: Cut faces show a breccia of dark and light colored subangular clasts in a fragmental matrix bearing sparse disseminated metal grains and metal aggregates. Light clasts range from showing only some delineated chondrules to showing well-delineated chondrules in a darker matrix. Dark clasts lack metal and appear featureless. In polished thin section, the stone is a fragmental chondritic breccia, consisting of high petrographic grade subangular chondrite lithic fragments from cm size to 10s of µm, set in a groundmass of fragmental chondritic debris with few intact chondrules. All clasts have a 20 µm dark brown rim. Olivine and pyroxene in clasts and in groundmass exhibit undulatory to mosaic extinction. Dark clasts appear to be shock-darkened. Fe oxidation is minor and limited to local alteration haloes around metal grains. Geochemistry: EPMA: olivine Fa30.35±0.65 (n=30); Ca-poor pyroxene Fs24.62±0.78, Wo1.91±0.28 (n=20); Ca-rich pyroxene Fs10.88±0.11, Wo43.92±0.72 (n=10) Classification: Ordinary chondrite LL4-6 breccia (S4) W1. Low observed metal content, EPMA olivine and pyroxene mineral compositions and magnetic susceptibility of log χ (× 10-9 m3/kg) = 3.73 are all consistent with LL chondrite. Clasts appear to be of LL chondrite material ranging from 4 to 6 grades, with some shock-darkened. Specimens: Type specimen ROM; main mass DGregory | ||||||||||||||||||||||||||||||||
| Data from: MB111 Table 0 Line 0: |
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| Institutions and collections |
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011) UWO: University of Western Ontario, Department of Earth Sciences, BGS 1026, 1151 Richmond St. N, London, Ontario, Canada N6A 5B7, Canada (institutional address; updated 18 Jul 2015) Aaronson: Sahara Overland Ltd., Harhora, Temara, 12000, Morocco (private address; updated 3 Jan 2010) DGregory: David Gregory, 230 First Avenue, Suite 108, St. Thomas, Ontario N5R 4P5, Canada (private address) |
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| References: | Published in Meteoritical Bulletin, no. 111, in preparation (2022)
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Geography:
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Statistics: This is 1 of 2012 approved meteorites from Morocco (plus 35 unapproved names) (plus 1 impact crater) | ||||||||||||||||||||||||||||||||