NWA 2921 (R3.8) - 44.4g Halved Individual with Primitive Clast

NWA 2921 was discovered during 2005 in the Sahara Desert, Africa. This meteorite has been classified as a Rumurutiite Chondrite, R3.8 with a Shock Rating of S1 and a Weathering Level of W3. The specimen below is a 44.4g Halved Individual displaying an obvious dark, unequilibrated, primitive clast. The clast deceivingly resembles a carbonaceous chondrite and appears to consist of chondrules and chondrule fragments set in a dark, fine-grained matrix. The darkening of the clasts in R-Chondrites is caused by the dispersion of sulphide grains. The dark clasts in Rumurutiites have been found to be considerably unaltered since their formation. In fact some clasts have been found to be as low as a 3.2 subgroup and probably represent the most primitive lithology yet found in the Rumurutiites. The Rumuruti parent-body underwent thermal metamorphism after formation and subsequently the other petrologic types 4, 5 and 6 have also been found in R-Chondrite meteorites. The parent-body later underwent impact processes which excavated and liberated this material including the primitive type-3 clasts. This is evident in the samples found here on Earth such as the individual below which are usually regolith/genomict breccias. (Click here for Meteorites Australia Glossary). This specimen is part of the Meteorites Australia Collection (MA.06.0020).

Mineralogical characterization of primitive, type-3 lithologies in Rumuruti chondrites.
A. Bischoff. (2.23 MB)

Rumuruti Chondrite: Origin and evolution of primitive components.
C. M. Lingemann, J. Berlin, and D. Stöffler. (11.5kb)

Dar al Gani 013: A new Saharan Rumurti Chondrite (R3-6) with highly unequilibrated (type 3) fragments. A. Jäckel, A. Bischoff, R.N. Clayton & T.K. Mayeda. (285kb)

NWA 2921 (R3.8) - 19.5g Half Individual
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NWA 2921 (R3.8) - 23.7g Half Individual
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NWA 2921 (R3.8) - 44.4g Individual before slicing.
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