Chondrite (meteorite) Bassikounou 69.70 gr.

 Chondrite (meteorite) Bassikounou

Location: Bassikounou, Hodh Ech Chargui, Mauritania, 15º47'N, 5º54'W

Fell: 2006, October 12; 04:00 UTC

Classification: Stone, Ordinary chondrite (H5)

Description: A fireball was witnessed in the area, but no records of the direction of movement were recorded. A single stone of 3165 g was found by A. Salem El Moichine, a local resident, on the same day at 13:00 hr local time, 11 km SE of Bassikounou. Numerous other finds define an 8 km long strewnfield. The 3165 g specimen is largely covered by black fusion crust. The interior is light gray. On the surface of the fusion crust there is some adherent soil material, some of which is bright red. Petrography: (E. Gnos, MHNGE; B. Hofmann, NMBE, M. Eggimann, Bern/NMBE): Mean chondrule size 0.35 mm (n=53). Metal abundance is 8 vol%, troilite 6.6 vol%. Mean plagioclase grain size is ~20 mm. Troilite is polycrystalline, rich in silicate inclusions, and shows diffuse boundaries to metal. Metal is partly rich in silicate- and troilite inclusions. Rare metallic Cu (10 mm) occurs at kamacite-taenite boundaries and in troilite. Some shock veins and no weathering products were observed. Mineral compositions: Olivine (Fa_18.6), pyroxene (Fs_16.3 Wo_1.1), plagioclase (An_13.7). Cosmogenic radionuclides: (P. Weber, PPGUN) Gamma-spectroscopy performed in December-January 2006 showed the presence of the following radionuclides: ⁴⁸V, ⁴⁶Sc, ⁵⁶Co, ⁵⁴Mn, ⁵⁸Co, ⁷Be, ⁵¹Cr, ⁵⁷Co, ²²Na, ²⁶Al and 60Co. Recalculated to 12 October 2006 22Na was 38.0±2.2 and ²⁶Al 31.5±2.1 (both dpm/kg), the activity ratio of 1.21 is fully consistent with a fall on that date. Shock stage: S2, weathering grade W0.(from Meteorical Bulletin 92). Oriented shape with fusion crust. The cube is 1 cm.

 Size:54.5x40.4x30 mm.

Weight:69.70 grams

CODE#9718