Okiem geologa (Norbert Brügge, Germany): http://www.b14643.de/Sahara/Kamil_Meteor_Crater/index.htm
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[MDB]
Gebel Kamil, East Uweinat Desert, Egypt;
Found: 19 Feb 2009 Classification: Iron meteorite (ungrouped)
History: A total of about 1600 kg of iron meteorite shrapnel (thousands of pieces), ranging in
mass from < 1 to 35,000 g, plus a single 83 kg individual completely covered with well developed
regmaglypts, was found in and around the 45 m diameter Kamil impact crater by an Italian-Egyptian
geophysical team in February 2009 and February 2010. Ca. 800 kg of the total mass observed in the field
(the regmaglypted individual inclusive) was recovered. The Kamil crater was identified by V. De Michele,
former curator of the Natural History Museum in Milan, Italy. The geophysical survey was carried out
within the framework of the "2009 Italian-Egyptian Year of Science and Technology".
Physical characteristics: A 634 g type specimen, measuring 88 x 70 x 55 mm, is flattened and
jagged shrapnel with a rough, dark-brown external surface. The surface originally sitting in the desert
soil shows some oxy-hydroxides due to terrestrial weathering.
Petrography: (M. D’Orazio, DST-PI; Luigi Folco, MNA-SI) Etched sections
show an ataxitic structure interrupted on a centimetric scale by crystals of schreibersite, troilite and
daubreelite enveloped in swathing kamacite. Kamacite spindles (20 ± 5 μm wide) nucleated on
tiny schreibersite crystals. The spindles form small aligned clusters and are rimmed by taenite. The
matrix is a duplex plessite made of approximately the same proportion of kamacite and taenite lamellae
(1-5 μm in thickness) arranged in a micro-Widmanstätten pattern. Many sections show, particularly
close to the external surface, shear dislocations offsetting the plessitic matrix and the crystals of
the accessory phases by several millimeters.
Geochemistry: (M. D’Orazio, DST-PI) Composition of the metal (ICP-MS;
D’Orazio and Folco 2003) is Co=0.75, Ni=19.8 (both in wt%), Cu=464, Ga=49, Ge=121, As=15.6, Mo=9.1,
Ru=2.11, Rh=0.75, Pd=4.8, Sn=2.49, Sb=0.26, W=0.66, Re=0.04, Ir=0.39, Pt=3.5, Au=1.57 (all in ppm).
Reference: D’Orazio M. and Folco L. (2003) Chemical analysis of iron meteorites by inductively
coupled plasma - mass spectrometry. Geostandards Newsletter: The Journal of Geostandards and Geoanalysis
27, 215-225.
Classification: (M. D’Orazio, DST-PI; Luigi Folco, MNA-SI) Iron meteorite (ungrouped),
Ni-rich ataxite, extensive shear deformation and low weathering.
Specimens: Type specimens: ca. 15 kg and one section at MNA-SI; ca. 5 kg at DST-PI.
Main mass of the recovered specimens at Egyptian Geological Museum (Mineral Resources Authority), Cairo,
Egypt.
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![Gebel Kamil (Iron-ung, ATAX) [Gilf al Kabir]](Egypt/GebelKamil_cs_247_0g_2.jpg)
![Gebel Kamil (Iron-ung, ATAX) [Gilf al Kabir]](Egypt/GebelKamil_cs_522_0g_2.jpg)
