
Researchers at Nagoya University said Monday they have discovered a natural diamond for the first time in Japan in volcanic rock in Ehime Prefecture. The announcement at the meeting of the Geological Society of Japan in Sapporo goes against an established theory that natural diamond does not occur in Japan. But the discovered diamond can not be observed even using a microscope as its size is about one part per thousand millimeters. In order to protect the extraction site, the group has declined to disclose it, saying, "A diamond should not to be produced commercially"...more...