SaU 005 - Martian Meteorite Fragment (77mg)
Discovered in 1999, at two locations, 1864 m apart, five grey-greenish stones were found that are macroscopically identical. Sayh al Uhaymir (SaU) 005 comprises one fragment of 547 g and two individuals of 561 and 236 g, which are partially covered by fusion crust and show regmaglypts.
This specimen weighs 77mg and measures ~ 6mm x 4mm x 2mm.
Mineralogy and classification (J. Zipfel, MPI): porphyritic texture with large olivine phenocrysts (Fo64–71) in a fine-grained groundmass of pigeonite (En61–70Wo6–13) and maskelynite (An51–65Or0.3–0.9); minor phases are augite, phosphates, and opaques; strongly shocked: mosaicism and planar deformation of olivines, twinning and fracturing of clinopyroxene, and up to millimeter-sized shock melted areas with quench textures are common; brown-orange ringlike structures formed by extremely fine-grained intergrowths of unidentified phases are abundant in impact-melt areas and pyroxenes; the meteorite is extremely fresh, with only a few of the larger cracks partially filled with calcite.
Bulk chemical analyses (B. Spettel, G. Dreibus, MPI; H. Palme, Köln), noble gas analyses (M. Paetsch, L. Schultz, MPI), and Sm-Nd systematics (E. Jagoutz, MPI): texture, bulk chemistry, noble gases, and Sm-Nd systematics indicate a very close relationship to Dar al Gani 476/489/670/735; however, on the basis of the distinct mineral chemistry and the place of find, simple pairing with those meteorites can be excluded.