CHWICHIYA 002

C3.00-ungrouped

standby for chwichiya 002 photo
click on photo for a magnified view

Found June 10, 2018
27° 06' 45.02" N., 11° 10' 25.2" W.

Numerous moderately weathered fragments and crusted stones having a combined weight of 644 g were found by Elho Sbiti in the Saguia el Hamra region of Western Sahara. Material was subsequently acquired by several meteorite dealers and a sample was sent to CEREGE (European Centre for Research and Teaching in Environmental Geosciences) for analysis and classification (J. Gattacceca et al.). The meteorite was designated Chwichiya 002 and determined to be an ungrouped carbonaceous chondrite of petrologic type 3.00. Additional fragments that were found as early as 2016, designated NWA 11750 (8.49 g) and NWA 12957 (43 g), were also classified at CEREGE (J. Gattacceca et al.) as C3.00-ungrouped. Based on very similar petrographic characteristics as well as broadly similar oxygen isotopes, they are considered to be likely paired with Chwichiya 002.

The meteorite is composed of relatively large chondrules (26 vol%, 480 [±300] µm) embedded in a dark, fine-grained matrix (74 vol%) together with accessory troilite and magnetite and rare FeNi-metal. An X-ray diffraction analysis was conducted at CEREGE (D. Borschnek), and both IR transmission and Raman spectroscopic analyses were conducted at the University of Grenoble, Institute of Planetology and Astrophysics (L. Bonal). Employing these techniques, they demonstrated that hydrous phases are virtually absent and that indigenous organic matter experienced peak heating less than that in Semarkona; therefore, the meteorite is consistent with petrologic type 3.00. An oxygen isotope analysis of Chwichiya 002 was conducted at CEREGE (J. Gattacceca and C. Sonzogni), and the single plot obtained falls within the CM field.

The specimen of Chwichiya 002 shown in the photos above and below is a 0.84 g fragment showing a broken surface with a few protruding chondrules set in a dark matrix. The outer surface shows slight wind abrasion. These excellent photos are shown courtesy of Azelmat Nor Eddine.

standby for chwichiya 002 photo
Photo courtesy of Azelmat Nor Eddine—Saharock Meteorites