June 30, 2012 15:54
Ordinary and diamonds are mined around the world in a special volcanic rock called kimberlite. As one of the possible states of an ordinary crystalline carbon (with a cubic crystal lattice), the diamonds formed at depths of 100 km, with very high pressures and temperatures. From there they go to the surface in the course of major volcanic eruptions, for a very short period of time. "With the rapid rise in diamond can retain their unique crystal structure that makes this mineral is the hardest of all known materials," — says Sonia Esperanza (Sonia Esperanca) from the Department of Geosciences of the U.S. National Science Foundation (NSF).
Since the beginning of XX century to the present in the world produced about 600 tons of diamonds, all of which are found in areas with very similar geological conditions. But Carbonado — kind of polycrystalline diamond black — clearly stands out from the picture: this rare mineral deposits in the Central African Republic and Brazil is not look like a place where diamonds are mined usual, writes sunhome.ru
A team of U.S. scientists led by Stephen Haggerty (Stephen Haggerty) and Mark Chancy (Mark Chance) stated that black diamonds are, apparently, of cosmic origin. Similar assumptions were expressed before — in 2004, researchers found in samples of some rare black diamond titanium and nitrogen, so far only be detected in the composition of meteorites.
At this time, experts from Brookhaven National Laboratory have found diamonds in the small admixture of hydrogen according to scientists, this suggests that they were formed in interstellar space, which is characterized by the presence of this gas. These data provide good evidence of the theory that black diamonds are formed as a result of a supernova explosion. Apparently, all the black diamonds of the Earth once formed part of a giant asteroid more than a kilometer in diameter, which collided with the Earth in prehistoric times.
Meanwhile, an extraterrestrial origin — not only the explanation of the origin carbonado. In 2003, in Minsk at the International Conference on Solid State Physics, a team of scientists from the Institute of High Pressure Physics in Troitsk, Institute of Geology, Komi Science Center in Syktyvkar and Brazil Universidade Federal de Minas Gerais compared the structural characteristics of synthetic and natural (Brazilian) carbonado. The report suggested that the origin of carbonado can be explained by purely worldly reasons. This theory says, in particular the discovery of black diamond in 1993 in an exotic volcanic rocks — the same rocks, the outputs of which are known on the eastern slope of the volcano Avachinsky (Kamchatka).