The research published by Gemmological Institute of America says that blue diamonds may get their attractive blue colour due to boron atoms that ancient oceans’ floors contained.
Blue diamond with inclusions Image credit: GIA
GIA has been examining 46 type IIb diamonds with inclusions submitted to the lab over two years. According to the research, after studying the inclusions the scientists were able to find the original stone and conclude that such diamonds were formed very deep in the earth at extremely high pressures. The minimal depth for formation of such diamonds was at – 410 km. The diamonds are said to be grown in the ocean crust. Borum is believed to be brought to the lower mantle, where it helped to form diamonds, because of the movements of Earth’s tectonic plates.
The study is of importance to the industry as it was believed that there were no large gem quality diamonds deep in the earth. This research shows that most large and relatively pure diamonds are superdeep.
The study will be presented at GIA’s International Gemological Symposium in October.
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