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Northwest Africa 13917 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 13917 This is an OFFICIAL meteorite name. Abbreviation: NWA 13917 Observed fall: No Year found: 2020 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 85 approved meteorites (plus 1 unapproved name) classified as Winonaite. [show all] Search for other: Primitive achondrites, Winonaites | ||||||||||||||||||||||||||||||
Comments: | Approved 6 May 2021 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 110:
Northwest Africa 13917 (NWA 13917) (Northwest Africa) Purchased: 2020 Classification: Primitive achondrite (Winonaite) History: Purchased from Morocco in September 2020 and January 2021. Physical characteristics: Several identical appearing stones found together -- the largest of which are individuals weighing 1.6 kg, 1.4 kg, and 1.2 kg. Saw-cut surface shows abundant fine-grained metal and sulfide set in a mosaic of brown and gray silicate minerals. A prominent metal vein 2 mm thick and several cm in length crosscuts the deposit sample slice. Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows a texturally equilibrated mosaic of enstatite and diopside with grain size in the range 100-300 μm, many triple junctions are present. Forsterite is ubiquitous but is significantly less abundant than the pyroxenes. Kamacite, taenite, and troilite make up approximately 10% of this meteorite, most grains are 100-300 μm in diameter. A phosphate phase was detected. No feldspar was observed in the microprobe mount. Geochemistry: (C. Agee UNM) Forsterite Fa4.0±0.0, Fe/Mn=16±0, n=2; enstatite Fs4.7±0.2Wo1.9±0.2, Fe/Mn=13±1, n=3; diopside Fs1.3±0.4Wo44.8±0.3, Fe/Mn=13±7, n=4. Oxygen isotopes (K. Ziegler, UNM): 3 acid-washed fragments analyzed by laser fluorination gave δ18O=4.959, 5.107, 5.236; δ17O=2.055, 2.179, 2.232; Δ17O=-0.563, -0.518, -0.533 (linearized, all per mil, TFL slope=0.528). Classification: Primitive achondrite (Winonaite) Specimens: 67.9 g on deposit at UNM. Mark Lyon holds the main masses. | ||||||||||||||||||||||||||||||
Data from: MB110 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||||
Institutions and collections |
UNM: Institute of Meteoritics
MSC03 2050
University of New Mexico
Albuquerque NM 87131-1126
USA, United States; Website (institutional address; updated 12 Feb 2015) |
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Catalogs: |
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References: | Published in Gattacceca J., McCubbin F.M., Grossman J., Bouvier A., Chabot N.L., D'Orazio M., Goodrich C., Greshake A., Gross J., Komatsu M., Miao B., and Schrader D. (2022) The Meteoritical Bulletin, No. 110. Meteorit. Planet. Sci. 1-4
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |