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Northwest Africa 4964 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 4964 This is an OFFICIAL meteorite name. Abbreviation: NWA 4964 Observed fall: No Year found: 2007 Country: (Northwest Africa) Mass: 456 g | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 91 approved meteorites classified as CK3. [show all] Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 3), CK chondrites, CK3 chondrites, and CV-CK clan chondrites | ||||||||||||||||||||||||||||
Comments: | Approved 31 May 2016 | ||||||||||||||||||||||||||||
Writeup |
Writeup from MB 105:
Northwest Africa 4964 (NWA 4964) (Northwest Africa) Purchased: 2007 Classification: Carbonaceous chondrite (CK3) Petrography: (K. Metzler, IfP) Chondrules and CAIs are embedded into a fine-grained brownish matrix. The matrix consists mostly of equilibrated Fe-rich olivine grains, interspersed with magnetite nodules. The mean apparent chondrule diameter is 1.13±0.69 mm (0.47-3.83 mm; n=31). Chondrules with igneous rims occur and CAIs up to 1.3 cm are observed. Geochemistry: The composition of matrix olivine is Fa33.8±0.6 (Fa32-35; n=16), while olivine in chondrule cores retained its original Mg-rich composition. Random olivine measurements revealed Fa30.7±5.9 (Fa13-35; n=22). Low-Ca pyroxene (En95-98Fs1-4 Wo1; n=5) mainly occurs in chondrules. Most pyroxene grains outside of chondrules are Ca-rich (En36-42Fs7-14 Wo49-51; n=7). The compositional range of feldspar (n=4) is An21-31. Magnetite is the most abundant opaque phase and shows significant concentrations of elements other than Fe (n=3): MgO 0.8-0.9 wt%; Al2O3 3.2-3.6 wt%; TiO2 0.8-0.9 wt%; Cr2O3 2.6-3.7 wt%; NiO 0.3-0.4 wt%. Classification: CK chondrite based on mineral chemistry. Petrologic type 3 based on the chemical variation of olivine and pyroxene. | ||||||||||||||||||||||||||||
Data from: MB105 Table 0 Line 0: |
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Institutions and collections |
IfP: Institut für Planetologie, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany (institutional address; updated 23 Jan 2012) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 105, MAPS 52, 2411, September 2017. http://onlinelibrary.wiley.com/doi/10.1111/maps.12944/full
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Geography: |
Statistics: This is 1 of 9933 approved meteorites from (Northwest Africa) (plus 1837 unapproved names) |