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Northwest Africa 13649 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 13649 This is an OFFICIAL meteorite name. Abbreviation: NWA 13649 Observed fall: No Year found: 2020 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 392 approved meteorites classified as Howardite. [show all] Search for other: Achondrites, HED achondrites, and Howardites | ||||||||||||||||||||||||||||
Comments: | Approved 16 Jan 2021 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 110:
Northwest Africa 13649 (NWA 13649) (Northwest Africa) Purchased: 2020 Oct Classification: HED achondrite (Howardite) History: The meteorite was purchased from a dealer in Tindouf, Algeria. Physical characteristics: Dark brownish rock without fusion crust. Exposes fresh dark grayish interior. Petrography: The meteorite is a polymict fragmental breccia composed of a large varitey of mineral and few up to 2 mm sized coarse-grained basaltic clasts set into a fine-grained clastic groundmass. Predominant minerals are diogenetic low-Ca pyroxene (about 40 vol%), more Fe-rich low-Ca pyroxene, Fe-rich low-Ca pyroxenes with augite exsolution lamellae, magmatically zoned low-Ca pyroxene, and calcic plagioclase all with highly variable grain sizes. Diogenetic low-Ca pyroxenes are up to 1 mm in size. Minor phases include silica, chromite, ilmenite, FeS, and metallic iron. The meteorite is highly shocked and contains shock melt veins; plagioclase is completely converted into maskelynite. Geochemistry: eucritic low-Ca pyroxene: Fs62.8±1.1Wo2.6±0.4 (Fs60.8-63.9Wo2.2-3.7, n=13, FeO/MnO=28-31); augite exsolution lamellae: Fs27.8±0.6Wo41.6±0.5 (Fs26.7-28.7Wo40.7-42.4, n=13, FeO/MnO=24-31); low-Ca-pyroxene: Fs39.2±0.2Wo2.6±0.1 (Fs39.0-39.5Wo2.4-2.7, n=7, FeO/MnO=25-28); zoned low-Ca-pyroxene: Fs26.2±4.6Wo2.7±0.1 (Fs22.0-34.2Wo2.4-2.9, n=10, FeO/MnO=26-32); diogenetic low-Ca pyroxene: Fs29.9±0.2Wo3.0±0.1 (Fs29.4-30.1Wo2.9-3.1, n=7, FeO/MnO=25-27); calcic plagioclase: An86.6±4.9 (An80.9-92.8, n=12) | ||||||||||||||||||||||||||||
Data from: MB110 Table 0 Line 0: |
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Institutions and collections |
MNB: Museum für Naturkunde, Invalidenstraße 43, D-10115 Berlin, Germany (institutional address; updated 24 Dec 2011) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 110, in preparation (2021)
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Geography: |
Statistics: This is 1 of 7579 approved meteorites from (Northwest Africa) (plus 1969 unapproved names) |