Northwest Africa 1465|
Carbonaceous chondrite (CV3 anomalous)
Many pieces totalling 3000 g and mostly covered with fusion crust were found in 2001 by
anonymous finder in the Western Saharan desert. Classification and mineralogy (A. Greshake,
MNB and M. Kurz, Kurz): a type 3 carbonaceous chondrite with chondrules, mineral fragments,
and refractory objects in a compact anhydrous matrix of Fe-rich olivine (Fa43-57.6), Ca-rich
pyroxene, enstatite, forsterite, troilite, magnetite, FeNi-metal, and weathering products;
olivine, Fa5.5 (range Fa0.4-41.9); pyroxene, Fs2.8 (range Fs0.8-5.5); shows a strong foliation
defined by flattened chondrules and refractory objects; the sample contains cm-sized
Ca,Al-rich inclusions and large inclusions of dark material (Greshake et al., 2003); oxygen
isotope composition of the bulk meteorite (R. Clayton and T. Mayeda, UChi): ?18O = 4.89‰,
?17O = 0.71‰; oxygen isotope composition of dark material, ?18O = 13.08‰, ?17O = 5.83‰., is
not in equilibrium with the host meteorite. Shock stage, S4; degree of weathering, W3.
Specimens: type specimen, 21.8 g, and one polished thin section, MNB; main mass with anonymous finder.