Description
On offer: a 2.88g fragment of an amazing classification. One of the largest fragment available.
Dimensions: ~18 x 12 mm
What you get: this 2.88g fragment, a plastic box with label at the back, a signed Certificate of Authenticity.
Type: C3 ungrouped chondrite
Country: Morocco
Date of find: 2018
Total mass: 32.2 g
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.