2.55g CR2 Carbonaceous Chondrite Meteorite End Cut I NWA 7020
|Northwest Africa 7020|
Name: Northwest Africa 7020
This is an OFFICIAL meteorite name.
Abbreviation: NWA 7020
Observed fall: No
Year found: 2011
Country: (Northwest Africa)
Mass: 715 g
This is 1 of 182 approved meteorites classified as CR2. [show all]
Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 2), and CR chondrites
|Comments:||Approved 22 Oct 2013|
Writeup from MB 102:
Northwest Africa 7020 (NWA 7020)
Purchased: 2011 Feb
Classification: Carbonaceous chondrite (CR2)
History: Purchased by Blaine Reed from a Moroccan dealer at the Tucson Gem and Mineral Show in February 2011.
Petrography: (A. Irving and S. Kuehner, UWS) Fairly closely-packed, medium-sized (typically 0.4 to 0.7 mm) chondrules and rare fine-grained CAI in a red to brown stained matrix containing kamacite, pentlandite and possible cronstedtite-tochilinite (based on EMPA spectra). Some chondrules are partially rimmed by kamacite. CAI contain spinel partially rimmed by gehlenite and rare Al-diopside.
Geochemistry: Olivine (Fa1.8-58.1, n=8, Cr2O3 in ferroan olivine 0.34-0.42 wt.%, n=6), orthopyroxene (Fs1.3-1.5Wo0.7-0.9), subcalcic augite (Fs4.6Wo28.5), augite (Fs1.6-3.3Wo44.1-39.2). Oxygen isotopes (R. Tanaka, OkaU): analyses of acid-washed subsamples by laser fluorination gave δ17O -2.101, -3.022; δ18O 1.026, -0.014; Δ17O -2.643, -3.019.
Classification: Carbonaceous chondrite (CR2).
Specimens: The main mass is held by Reed. A total of 22.8 g of material and one polished thin section are on deposit at PSF.
PSF: Planetary Studies Foundation,10 Winterwood Lane, Unit B, Galena, Illinois 61036-9283, United States; Website (institutional address; updated 1 Dec 2011)
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012)
OkaU: Institute for Study of the Earth's Interior, Okayama University, Misasa Tottori 682-0193, Japan (institutional address)
Reed: Blaine Reed, P.O. Box 1141, Delta, CO 81416, United States; Website (private address)
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