Description
Chwichiya 003 (reclassification)
Petrography: (J. Gattacceca, CEREGE) XRD over a ~1 cm2 area on a polished section (D. Borschnek, CEREGE) does not reveal the presence of hydrous phases (serpentine, tochilinite) typically observed in type 2 chondrites using the same experimental setup.
Geochemistry: Oxygen isotopic composition (J. Gattacceca, C. Sonzogni, CEREGE) from analysis of one 1.5 mg aliquot of a powdered 208 mg bulk sample is δ17O=-2.47‰, δ18O=3.63‰ , Δ17O=-4.36‰ (slope 0.52, analytical uncertainties 0.08‰, 0.12‰, 0.01‰ respectively).
Classification: Carbonaceous chondrite (C3-ung). The petrography is similar to CM chondrites, but there is no evidence for significant aqueous alteration (XRD, and elevated total in the matrix analyses compared to CM2 chondrites, as reported in Met. Bull. 108). Oxygen isotopic composition is at the limit between the CO and CM fields.
