NWA 8534, Rare Carbonaceous CM1/2, Micromount



A few very small fragments of a carbonaceous chondrite were recovered out of the Saharan Desert in Morocco in 2014. Intensive study by scientists determined that it is a rare type CM1/2 meteorite that is one of only 22 known of this type. It was officially classified as NWA 8534. The vast majority of this type of meteorite are Antarctics which are locked away in institutions. There are only three non-Antarctic CM1/2 meteorites available to collectors and the combined total weight of these meteorites about a quarter pound. This is one of the hardest to acquire types for type-collectors.

Refer to the photo. The black centimeter cube is shown for scale and is not included. You are purchasing a single small fragment like the one shown. Your purchase will include a labeled gemjar for safe storage.

From the Meteoritical Bulletin entry on NWA 8534 :

Northwest Africa 8534 (NWA 8534)

Purchased: 2014 Jun 12

Classification: Carbonaceous chondrite (CM1/2)

History: Purchased 12 June 2014 in Morocco.

Physical characteristics: Many identically appearing small fragments, the largest being 2.6 g, with black, fresh fusion crust. Broken surface reveals black, uniform, very fine-grained texture, rare sub-mm CAIs, with no visible chondrules.

Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows a matrix (80-90%) dominated by (Mg,Fe)-rich phyllosilicates, with scattered, small (~250 μm), mostly irregularly shaped chondrules, many of which contain secondary alteration phases. There is no mesostasis in any chondrule; they are all altered. This meteorite is transitional between CM1 and CM2. There is more fine-grained (80-90%, dominantly phyllosilicate) matrix than in CM2, but less than CM1. Calcium carbonate, (Ca,Mg)-carbonate, sulfides, and Fe-oxides are ubiquitous.

Classification: Carbonaceous chondrite (CM1/2), the petrologic type 1/2 is based on the relatively low abundance of chondrules and refractory inclusions, the high abundance of hydrous phases, and high volume percentage of matrix. It is also based on the mean value of eight oxygen isotope analyses that plots outside the field of CM2.