Northwest Africa 15246 (NWA 15246)

(Northwest Africa)

Purchased: 26 Apr 2013

Classification: Ordinary chondrite (L6)

History: A 19.9 g piece of the meteorite was sent to Cascadia by John Shea, who purchased the sample on April 26, 2013 from Gary Fujihara of Big Kahuna Meteorites, who in turn purchased the sample on February 25, 2013 from Youssef Ait El Caid, Zagora, Morocco as part of a 3.2kg lot of unclassified meteorites.

Physical characteristics: Physical Characteristics: The exterior of the stone is covered by a dark brown weathered fusion crust. Cut faces are a light-to-medium brown with cream-colored areas indicative of poorly-defined chondrules and inclusions. A black vein cuts across the sample, and metal and sulfide grains are visible.

Petrography: (M. Hutson, A. Ruzicka, Cascadia): The sample is coarse-grained in thin section, with only a few readily distinguished chondrules. Along one edge of the section is an igneously-textured inclusion in the form of a segment of a circle with the edge of the segment along the edge of the section; the circle edge is 6.8 mm long. Two black veins cut the section. The veins contain numerous clasts of several phases, including majorite and ringwoodite, set amidst a sulfide-rich matrix. Coarse maskelynite is present in the meostases of both the large inclusion and a few of the larger chondrules.

Geochemistry: Olivine: Fa_24.9±0.4, N=22; low-Ca pyroxene: Fs_21.0±0.4Wo_1.4±0.3, N=12.

Classification: Ordinary chondrite (L6) based on mineral chemistry and texture.

Specimens: Cascadia holds 18.1 g in one piece, as well as a polished thin section; JShea holds the main mass.