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| Northwest Africa 15548 | |||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 15548 This is an OFFICIAL meteorite name. Abbreviation: NWA 15548 Observed fall: No Year found: 2021 Country: (Northwest Africa) Mass:  106.9 g | ||||||||||||||||||||||||
| Classification history: |
This is 1 of 6 approved meteorites classified as Mesosiderite-A2. [show all] Search for other: Class A mesosiderites, Mesosiderites, and Metal-rich meteorites | ||||||||||||||||||||||||
| Comments: | Approved 7 May 2023 | ||||||||||||||||||||||||
| Writeup |
Writeup from MB 112:
Northwest Africa 15548 (NWA 15548) (Northwest Africa) Purchased: 2021 Nov Classification: Mesosiderite (group A2) History: Jason Whitcomb purchased a single stone from an Algerian dealer. Place and date of find, unknown. Petrography: (C. Herd, UAb) Optical and microprobe examination of a polished thin section shows orthoyroxene mineral grains up to 1 mm across with <100 μm wide low-Ca rims, in a fine-grained matrix consisting of low-Ca pyroxene, plagioclase, minor high-Ca pyroxene, troilite, chromite, ilmenite, merrillite, and silica. Kamacite is present at ~40 vol% abundance and occurs as mm-scale segregated areas between the silicates. Very fine sulfides are disseminated throughout the matrix. Minor iron staining is present. Geochemistry: (C. Herd and A. Locock, UAb) Data obtained by EMP examination of carbon-coated thin section: opx mineral clast cores: Fs23±3En76±4Wo1.2±0.4, molar Fe/Mn = 32±2, molar Fe/Mg = 0.31±0.06 (n=13); low-Ca matrix pyroxene: Fs36±4En61±5Wo3.2±1.4, molar Fe/Mn = 28±2, molar Fe/Mg = 0.60±0.09 (n=31); high-Ca matrix pyroxene: Fs17En40Wo43 (n=1); plagioclase Ab8.6±1.7An91.2±1.8Or0.2±0.1 (n=23). Classification: Mesosiderite, A2. Classification based on the proportions of pyroxene and plagioclase, and the moderately recrystallized texture. Specimens: Type specimen of 20.7 g, including one thin section, is at UAb. Main mass with Whitcomb. Writeup from MB 112: Northwest Africa 15548 (NWA 15548) (Northwest Africa) Purchased: 2021 Nov Classification: Mesosiderite (group A2) History: Jason Whitcomb purchased a single stone from an Algerian dealer. Place and date of find, unknown. Petrography: (C. Herd, UAb) Optical and microprobe examination of a polished thin section shows orthoyroxene mineral grains up to 1 mm across with <100 μm wide low-Ca rims, in a fine-grained matrix consisting of low-Ca pyroxene, plagioclase, minor high-Ca pyroxene, troilite, chromite, ilmenite, merrillite, and silica. Kamacite is present at ~40 vol% abundance and occurs as mm-scale segregated areas between the silicates. Very fine sulfides are disseminated throughout the matrix. Minor iron staining is present. Geochemistry: (C. Herd and A. Locock, UAb) Data obtained by EMP examination of carbon-coated thin section: opx mineral clast cores: Fs23±3En76±4Wo1.2±0.4, molar Fe/Mn = 32±2, molar Fe/Mg = 0.31±0.06 (n=13); low-Ca matrix pyroxene: Fs36±4En61±5Wo3.2±1.4, molar Fe/Mn = 28±2, molar Fe/Mg = 0.60±0.09 (n=31); high-Ca matrix pyroxene: Fs17En40Wo43 (n=1); plagioclase Ab8.6±1.7An91.2±1.8Or0.2±0.1 (n=23). Classification: Mesosiderite, A2. Classification based on the proportions of pyroxene and plagioclase, and the moderately recrystallized texture. Specimens: Type specimen of 20.7 g, including one thin section, is at UAb. Main mass with Whitcomb. | ||||||||||||||||||||||||
| Data from: MB112 Table 0 Line 0: |
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| Institutions and collections |
UAb: 1-26 Earth Sciences Building, University of Alberta, Edmonton, AB, T6G 2E3, Canada, Canada; Website (institutional address; updated 17 Oct 2011) |
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| Catalogs: |
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| References: | Published in Meteoritical Bulletin, no. 112, in preparation (2023)
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| Geography: |
Statistics: This is 1 of 9092 approved meteorites from (Northwest Africa) (plus 1875 unapproved names) | ||||||||||||||||||||||||