But we know they are formed of carbon atoms coming together under intense pressure and heat to form crystals. The stones that we mine today are ... but they are much rarer than yellow ones. A green ...

Many minerals form beautiful crystals ... There are a number of semiprecious gems, many quite beautiful, but diamonds, rubies, sapphires, and emeralds continue to qualify as "precious." ...

These mineral flecks, identified as calcium ... discoveries lies in the challenge of locating super-deep diamonds. These gems form under extreme conditions, and there's no easy way to predict ...

"The occurrence of ringwoodite together with the hydrous phases indicate a wet environment at this boundary," a team of researchers led by mineral physicist Tingting Gu of the Gemological Institute of ...