Diamonds from the Popigai impact crater, RussiaArvisp (1626837) writes "The deposits of super solid diamond — impactites — were discovered in the Popigai Basin by Soviet geological expedition in the mid-1960s. The scientists determined that the deposit appeared about 35 million years ago, after an asteroid, about seven kilometers in diameter, rammed into Earth. According to Gazeta.ru, Soviet specialists were busy with producing synthetic diamonds during the 1960s, so the studies of impactites were stopped, the information about their deposit was classified.
In late 1970s, it became known that the abrasive qualities of Popigai diamonds were significantly higher than that of synthetic and natural stones. About three years ago, Russian experts together with their Ukrainian colleagues conducted a series of experiments to study the properties of these minerals. It turned out that impactites differed from conventional diamonds considerably. Moreover, diamonds with such properties have never been found anywhere else in the world. Therefore, experts believe that the Popigai diamonds are of extraterrestrial origin. Nikolai Pokhilenko said that the mineral originated from graphite as a result of a meteorite impact, when pressure reached 1.5 million atmospheres and temperature went up to 3,000 degrees Centigrade.
Diamonds at Popigai Astroblem in Siberia are 'twice as hard' as normal, making them ideal for high-precision scientific instruments and industry"
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