![]() Seymchan is considered to be a stable and rust-resistant pallasite. Before the discovery of its pallasitic structure, it had been classified as IIE anomalous coarse octahedrite. Seymchan belongs to the main pallasite group, but it is considered unusual because of its high iridium content. The pallasitic structure had not yet been discovered in studies of small sections of the initial mass, composed only of metal. ![]() Olivine crystals represent about 37 of the weight of the meteorite. Remarkably, approximately 20% of the new specimens contained olivine crystals, revealing the silicate nature of the meteorite. Brahin is a Main Group pallasite, with angular shaped olivine embedded in an iron-nickel matrix. The main mass was given to the Academy of sciences of the USSR.ĭuring a new expedition in 2004, Dmitri Kachalin recovered approx. A second specimen of 51 kg (112 lb) was found with a mine detector at a distance of 20 m from the first in October 1967 by I.H. Of the 60,000 or so meteorites that have been discovered on Earth, at least 175have been identified as originating from the planet Mars. The meteorite is considerably weathered, with limonitic staining and patches of brown limonite throughout the section. The mass was a triangular thumb print meteorite lying among the stones of the river bed. A Mars meteorite stone (shergottite) weighing 245.4 grams. around isolated metal pools (UREY, 1966) and at, or near, the centers of cores (WAHL, 1965 BUSECK and GOLDSTEIN, 1969). The main mass of 272.3 kg (600 lb) was found during a study made in June 1967 by the geologist FA Mednikov. The olivine-metal meteorites are widely believed to have formed at the core-mantle interface of an asteroidal- sized core (ANDERS, 1964) although other locations have also been considered, viz. ![]() Seymchan is a pallasite meteorite found in the dry bed of the river Hekandue, a left tributary of river Jasačnaja in the Magadan district, Russia, near the settlement of Seymchan, in June 1967. All iridium (Ir) in lunar meteorites derives from asteroidal meteorites (e.g., chondrites, iron meteorites) that strike the lunar surface. The Cr/Sc ratio (chromium/scandium) is a proxy for the olivine/pyroxene ratio. Magnificent Seymchan meteorite with olivine, silver rhodium protection. The three highest-Sm/Th meteorites with <30 mg/g Sc are enriched in Sm from terrestrial weathering processes.
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