[meteorite-list] AD-New rare pallasite
From: Gary Fujihara <fujmon_at_meteoritecentral.com>
Date: Tue, 21 Apr 2015 07:18:20 -1000 Message-ID: <F19B446D-9A70-4E6C-A229-E059DBB6E70C_at_mac.com> Aloha Meteorite afficianadoes, The Big Kahuna has acquired some of the rarest pallasite meteorites known, in a recent acquisition. In November, 2007, Brahim Oubadi from Bouanane, Morocco, was searching for meteorites on the Oued Bourdim wadi. He found many small pieces of a heavy rock (for its size) that looked different from the surrounding materials. Over the next few years, Mr. Oubadi found approximately 400 g. He sold the stones to a meteorite dealer in Boudnib, and they were subsequently sold at the Tucson Gem and Mineral show where they were nicknamed "Boudnib". Physical characteristics: Many small stones totaling 393 g. The largest are 48.9 g and 68.9 g, whereas the majority are <10 g. Exterior of the stones is dark colored and the olivines are sand blasted with a waxy luster. Fusion crust largely absent, though there are a few remaining patches on the metal. Medium to low weathering. Petrography: (L. Garvie, ASU). A 3 ? 2 cm sawn surface of the 48.9 g stone shows 30 areal% metal. Olivine grains highly fractured, rounded and <1 cm across. Swathing kamacite to 1 mm thick and discontinuous. There are a few areas of swathing schreibersite to 0.5 mm thick. Ropey schreibersite also present within the swathing kamacite. Troilite rare, occurring as spheres to 1 mm in the olivine. The bulk of the metal has a martensite decomposition structure (Novotny et al., 1982), composed of Widmanst?tten alpha platelets (typically <100 ?m long) in fine plessite matrix; schreibersite 10 to 50 ?m is common. The platelets are surrounded by taenite rims. Two chromite grains present. Excluding the 48.9 g stone, six additional stones were sectioned, polished, and etched - all showed metal with the martensite decomposition structure. Terrestrial Fe oxides locally replacing swathing kamacite and troilite. Montana Meteorite Laboratory cut and polished a 79g fragment into an assortment of slices and one endcut. All specimens are stunningly beautiful and would certainly make a great addition to any collection. The fact that this meteorite is a new member, and one of only five known of the Eagle Station pallasite grouplet makes it very rare and desirable. The unique etch pattern makes them visually striking as well. Limited supply, first come-first served, and about half of the material can be seen on this webpage: http://bigkahuna-meteorites.com/OuedBourdim.html Mahalo for looking and have a great day/evening! Gary Fujihara Big Kahuna Meteorites Inc. PO Box 4175, Hilo, HI 96720 (808) 640-9161 http://bigkahuna-meteorites.com/ http://www.ebay.com/sch/fujmon/m.html Received on Tue 21 Apr 2015 01:18:20 PM PDT |
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