Diamond is the hardest substance found in nature. It is pure carbon formed deep in the earth's core into a hard and rare crystal . Diamonds are mined around the world. In its "rough" form, a diamond bears little resemblance ro the sparkling treasure it will become. A diamond's true beauty must be revealed through the hands of a skilled diamond cutter. Diamonds can be cut and polished in a variety of shapes like round, princess, pear, heart, marquise, oval, or other specialty cuts.Rough and polished diamonds are bought and traded in the Antwerp diamond market by dealers and brokers from all over the world. Diamonds are evaluated for sale using the 4 C's of Cut, Color, Clarity and Carat weight. Trained diamond graders use these four characteristics to determine the price, rarity, and beauty of every diamond.