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Northwest Africa 14260 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 14260 This is an OFFICIAL meteorite name. Abbreviation: NWA 14260 Observed fall: No Year found: 2017 Country: (Northwest Africa) Mass: 314 g | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 27 approved meteorites classified as R3-5. [show all] Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3) | ||||||||||||||||||||||||||||
Comments: | Approved 17 Oct 2021 | ||||||||||||||||||||||||||||
Writeup |
Writeup from MB 110:
Northwest Africa 14260 (NWA 14260) (Northwest Africa) Purchased: 2017 July 13 Classification: Rumuruti chondrite (R3-5) History: Single stone purchased by Mr. Jasper Spencer from a Moroccan meteorite dealer in Morocco. Mr. Spencer sent a slice to Cascadia in 2019 for classification. Physical characteristics: Physical Characteristics: The slice received by Cascadia has outer edges of brown to orange weathered fusion crust. Light colored chondrules are visible on the cut surface, including three bleached chondrules set against a brown background (host lithology). A dark clast is truncated by the outer surface of the slice; two orthogonal straight edges (1.5 × 1 cm across) of the dark clast intersect the interior brown host lithology. Four smaller darks clasts (one 0.6 cm long, the others <=0.3 cm long) are visible inside the host lithology. Petrography: (M. Hutson, A. Ruzicka, Cascadia): Phases observed in thin section include olivine, low-Ca pyroxene, high-Ca pyroxene, plagioclase feldspar (all <40 μm across), feldspathic glass, chlor-apatite, chromium spinel containing up to 5.7 wt% TiO2, aluminous spinel, ilmenite, pyrrhotite, and pentlandite. In thin section, the sample consists of a mix of chondrule-bearing clasts of various sizes, some distinct, others less so. Some clasts with distinct boundaries are fragments of breccias, as they contain smaller distinct clasts. One example is Clast 2, which is an unequilibrated clast (~0.4 × 0.9 mm) with chondrules set in a fine-grained matrix composed mainly of olivine and feldspathic material; one aluminous spinel was observed in the matrix of this clast. Clast 2 is embedded in a larger (1.3 × 0.8) well-defined clast containing chondrules with zoned olivine, but a less distinct and coarser matrix than Clast 2. Other clasts include entirely equilibrated material (Clast 1, 2.5 × 2 mm), and a roughly equant (~1.2 × 1.2 mm) highly unequilibrated clast (Clast 3) containing a refractory inclusion that contains Al-Ti-clinopyroxene, aluminous spinel, olivine, and a poorly characterized Na-Fe-Mg-K-aluminosilicate. Small shards of apparent shock melt are visible in thin section. One such shard, Clast 4, is comprised of strongly zoned olivine grains, some skeletal, set in a crystallite-filled glassy matrix; three of the larger zoned olivine grains are truncated by the clast boundary. Chondrules in the various clasts are < 0.5 mm across, but these are mixed with larger chondrules, including two that are >= 2 mm across. Both of the large chondrules are slightly ovoid; BC1 (2.5 × 2.0 mm) contains equilibrated olivine and pyroxene, BC2 (2.7 × 2.1 mm) is composed mainly of Mg-rich zoned porphyritic olivine grains. There is a rough alignment of elongated clasts and chondrules across the section. Geochemistry: Mineral compositions and geochemistry: All areas combined: Olivine Fa30.7±14.3, N=191; Low-Ca pyroxene: Fs12.0±9.3Wo1.4±1.1, N=43, High-Ca pyroxene: Fs12.1±7.8Wo43.5±3.2, N=37; Plagioclase feldspar: Ab85.2±1.6Or9.8±2.1, N=10; Cr-spinel: MG#=3.1±0.5, CR#=83.2±1.1, N=5. Chondrule BC1: Olivine Fa38.8±0.1, N=4. Chondrule BC2: Olivine Fa13.2±11.8, N=15. Clast 1: Olivine Fa39.4±0.4, N=11. Clast 2: Olivine Fa24.6±17.5, N=11, single spinel grain: MG#=44.5, CR#=0.25. Clast 3 (excluding refractory inclusion): Olivine Fa11.9±10.6, N=3. Refractory inclusion (in Clast 3): Olivine Fa19.4±15.9, N=4; High-Ca pyroxene: Fs5.5±2.5Wo39.4±3.2, N=4, with Al2O3=2.3-4.3 and TiO2=0.9-2.5; Spinel: MG#=41.4±2.0, CR#=0.9±0.1, N=3. Classification: R3-5 genomict breccia based on mineralogy, mineral compositions, plagioclase-feldspar grain size, and texture. Specimens: Cascadia holds 35.6 g in on piece, as well as a polished thin section and material in a stub. Mr. Jasper Spencer holds the main mass. | ||||||||||||||||||||||||||||
Data from: MB110 Table 0 Line 0: |
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Institutions and collections |
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011) |
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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 9927 approved meteorites from (Northwest Africa) (plus 1837 unapproved names) |