Ribbeck/Badania

Petrography: (A. Greshake, C. Hamann, L. Hecht, MNB) The meteorite is a coarse-grained achondritic breccia predominantly composed of large, up to 1.2 cm sized, mostly angular whitish enstatite grains, less abundant, up to 1.5 mm sized forsterite crystals, and minor sodic feldspar set in a fine-grained interstitial cataclastic matrix consisting of related material. Opaque phases include troilite, alabandite, oldhamite, heideite, keilite, djerfisherite, kamacite, and taenite. Enstatite and forsterite show pronounced undulatory extinction. All phases are intensely fractured and enstatite contains several sets of planar cracks. No diopside detected.

Geochemistry: Enstatite: Fs₀Wo_0.7±0.1 (Fs₀Wo_0.6-0.9, n=10); olivine: Fa₀, n=10; plagioclase: An_1.4-4.8Ab_93.1-96.2Or_2.0-2.4, n=5); troilite contains : 0.18±0.01 wt% Cr and 0.94±0.3 wt% Ti, N=3; kamacite contains : 4.65±0.11 wt% Ni, 0.94±0.2 wt% Co, and 0.07±0.01 Si, N=3; taenite contains : 32.4±0.3 wt% Ni, 0.56±0.2 wt% Co, and 0.10±0.01 Si, N=3

Physical characteristics: (A. Greshake, C. Hamann, L. Hecht, MNB) The various individuals show rounded, egg-shaped, and angular shapes, have a gray-white patchy appearance and are partly to fully covered by fresh, whitish to dark grayish, often intensely cracked fusion crust. In many cases, the fusion crust contains transparent, often highly vesicular areas that appear to cover the dull gray and dull white areas in the form of thin veneers or stringers of quenched melt. Some rocks are fragmented, thereby exposing the whitish interior with large mineral grains already visible to the naked eye.