History - What Is A Diamond?

The fiery brilliance of the diamond has made it the world's favorite jewel. The word comes from the Greek term adamas which means "unconquerable". The diamond is the hardest natural substance found on Earth. Diamond-tipped industrial tools can cut through granite as easily as a steel saw can cut through wood.

Diamonds are crystals of pure carbon that have been subjected to tremendous pressure and heat. This process is believed to have taken place deep in the Earth. Synthetic, or man-made, diamonds became possible in 1955, when the General Electric Company used laboratory equipment to subject graphite to great pressure and heat.

The weights of both gem and industrial diamonds are expressed in metric carats. One carat equals one fifth of a gram.