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Northwest Africa 7418 | |||||||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 7418 This is an OFFICIAL meteorite name. Abbreviation: NWA 7418 Observed fall: No Year found: 2012 Country: Mauritania Mass: ![]() | ||||||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 17 approved meteorites classified as LL6-melt breccia. [show all] Search for other: LL chondrites, LL chondrites (type 4-7), Melted chondrites, Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||||||||
Comments: | Approved 29 Sep 2013 | ||||||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 102:
Northwest Africa 7418 (NWA 7418) Mauritania Found: 2011 Classification: Ordinary chondrite (LL6, melt breccia) History: Discovered by local people in Mauritania in 2011, purchased in Nouadhibou in 2012 July. Physical characteristics: Three light-brown stones, partly covered by fusion crust, 215.7 g in total. Saw-cut surface shows breccia of fine-grained light brown matrix with darker angular clasts. Broken face shows waxy lustre. Magnetic susceptibility log χ = 3.09. Petrography: Microprobe examination of a thin section shows fine (mean, 40 μm) granophyric matrix of olivine, pyroxene and feldspar, bearing dominantly pyroxene (<0.8 mm), often with poikilitic olivine and feldspar, globular metal and troilite, and olivine (<0.3 mm). Rare relict chondrules are present. Geochemistry: (R. Bartoschewitz, Bart, P. Appel and B. Mader, Kiel) Olivine: Fa31.6-35.7, mean Fa32.4±1.0 (n=16), Fe/Mn=61±6 (n=14) and Fe/Mn=82±2 (n=2); low Ca pyroxene: Fs25.9-26.7Wo2.6-3.8, mean Fs26.2±0.3Wo3.3±0.5 (n=6); Ca-rich pyroxene: Fs11.2-13.9En46-47Wo39-42; feldspar: An11-14Or4-6; chromite: Cr/(Cr+Al) = 87, Fe/(Fe+Mg) = 88-91. Classification: Ordinary chondrite (LL6-melt breccia) with anomalous characteristics. Strong recrystallized texture of moderately equilibrated olivine composition, dominantly with LL-chondritic Fe/Mn, plus some grains above the LL ratio. Specimens: 20 g on deposit at Kiel, main mass Gren (100 g), 72 g with Bart, and 18 g with SBuhl. | ||||||||||||||||||||||||||||||||||
Data from: MB102 Table 0 Line 0: |
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Institutions and collections |
Kiel: Geologisches und Mineralogisches Museum, Institut für Geowissenschaften, Christian-Albrechts-Universität Kiel, Ludewig-Mayn-Str. 10, D-24118 Kiel, Germany, Germany (institutional address; updated 13 Sep 2013) Bart: Bartoschewitz Meteorite Laboratory, Weiland 37, D-38518 Gifhorn, Germany; Website (private address; updated 30 Nov 2019) Gren: Andreas Gren, Hamburg, Germany (private address) SBuhl: Meteorite Recon (Mr. S Buhl), Muehlendamm 86, 22087 Hamburg, Germany (private address; updated 14 May 2010) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 102, MAPS 50, 1662, September 2015
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Geography:![]() |
Statistics: This is 1 of 187 approved meteorites from Mauritania (plus 2 unapproved names) (plus 2 impact craters) |