A stone weighing ~15 g along with numerous smaller pieces (pers. comm.) were found at an undisclosed location, and this material was subsequently purchased by F. Kuntz in Rissani, Morocco. A sample was sent to CEREGE (European Centre for Research and Teaching in Environmental Geosciences) for analysis and classification (J. Gattacceca, D. Borschnek, C. Sonzogni, and D. Au Yang), and NWA 16000 was classified as an ungrouped type 3 carbonaceous chondrite.
The relatively fresh meteorite is composed of distinct, unequilibrated chondrules (olivine Fa0.9–62.9 mol%) measuring 390 (±240) µm, embedded together with CAIs (up to 100 µm) in a fine-grained matrix constituting ~81 vol%. Other phases present include sulfides, rare metal, and framboidal-like magnetite clusters (see image), the latter perhaps similar to framboidal pseudo-magnetite (wüstite) identified in a Ryugu sample by Kimura et al. (2022); notably, no phyllosilicates or other hydrous phases were identified in the NWA 16000 analysis. An oxygen isotope analysis shows that NWA 16000 plots with Ryugu samples and CI chondrites (see diagram below).
O-isotope Plot for CI1 Oued Chebeika and C3-ung NWA 16000
click on diagram for a magnified view
Diagram adapted from the Meteoritical Bulletin Oxygen Isotope Plots—The Meteoritical Society
The photo of NWA 16000 shown above is a 3.05 g slice, shown courtesy of F. Kuntz. The meteorite exhibits the typical features of this unique carbonaceous chondrite as demonstrated in the photo of multiple slices below.
click on diagram for a magnified view
Photo courtesy of Fabien Kuntz—WWMeteorites
