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Northwest Africa 10169 | |||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 10169 This is an OFFICIAL meteorite name. Abbreviation: NWA 10169 Observed fall: No Year found: 2015 Country: (Northwest Africa) Mass: 22 g | ||||||||||||||||||||||||||
Classification history: |
This is 1 of 330 approved meteorites (plus 2 unapproved names) classified as Martian (shergottite). [show all] Search for other: Martian meteorites | ||||||||||||||||||||||||||
Comments: | Approved 18 Jul 2015 | ||||||||||||||||||||||||||
Writeup |
Writeup from MB 104:
Northwest Africa 10169 (NWA 10169) (Northwest Africa) Purchased: Jan 2015 Classification: Martian meteorite (shergottite) History: The sample was found in the region of Layoune, and bought at the Tucson show by Luc Labenne from an anonymous Moroccan dealer. Physical characteristics: An uncrusted fragment with a blotchy appearance. Petrography: (R. Hewins, S. Pont, B. Zanda, MNHNP) The most abundant phase is olivine (~45%) which occurs as subhedral to euhedral crystals 100 μm to 1.5 mm in size. These contain Cr-rich spinel crystals and melt inclusions with pyroxene and plagioclase. The pyroxenes, pigeonite and augite, are distinguishable (with difficulty) in BSE and show neither zonation nor exsolution. The pigeonite envelopes olivine poikilitically, and is subophitic to plagioclase laths, or interstitial. The "plagioclase" is almost entirely free of fractures and is continuous like glass between the pyroxene grains. It is presumed to be maskelynite because it looks the same as glass identified as maskelynite by Raman spectroscopy in NWA 10171. Augite is interstitial but also occurs as large masses. Ti-rich spinel occurs in association with pyroxene and plagioclase. Minor phases include ilmenite. Geochemistry: Mineral compositions and Geochemistry: (R. Hewins, MNHNP) The olivine composition is Fo58.7±0.5Fa41.3±0.5, with an FeO/MnO ratio of 49.1±1.6, n=121. The pigeonite composition is En57.7±1.8Fs29.8±1.6Wo12.6±3.1, n=24, and FeO/MnO of 29.6±1.7; and the augite is En46.5±1.0Fs19.2±1.1Wo34.3±1.9, n=32 with an FeO/MnO ratio of 29.2±1.8. Spinel ranges from Sp14Cr79Usp3Mgt4 to Sp6Cr20Usp56Mgt18. Plagioclase is stoichiometric An52.7±1.6Ab44.9±1.3Or2.4±0.6. Classification: (R. Hewins and B. Zanda, MNHNP) The meteorite has SNC Fe/Mn ratios, maskelynite, and 43% olivine. It is classified as a lherzolitic shergottite. | ||||||||||||||||||||||||||
Data from: MB104 Table 0 Line 0: |
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Institutions and collections |
MNHNP: Museum National d'Histoire Naturelle, IMPMC-CP52, 57 rue Cuvier, 75005 Paris, France, France; Website (institutional address) USP: Museu de Geociências - USP Rua do Lago, 562 CEP: 05508-080 Butantã - SP Brazil, Brazil; Website (institutional address; updated 16 Feb 2024) Labenne: 23, rue de Esperance, 75013 Paris, France; Website (private address; updated 29 Aug 2012) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
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Geography: |
Statistics: This is 1 of 9921 approved meteorites from (Northwest Africa) (plus 1838 unapproved names) |