jewelry television Article
A mineral composed essentially of carbon that crystallizes in the “cubic,” or “isometric,” crystal system and is therefore singly refractive. By far the hardest of all known natural substances (10 on Mohs’ scale); only manmade Borazon and synthetic diamond are as hard. In its transparent form, it is the most cherished and among the most highly valued gemstones. It occurs in colors ranging from colorless to yellow, brown, orange, green, blue, and violet.
