The less color in a diamond, the more rare. Diamonds are graded by color, starting at D and moving through the alphabet to Z. While most diamonds appear white, virtually all display perceptible tins of color.
The better cut a diamond, the more brilliant. A diamond cut to correct proportions will give off an unrivaled radiance. Cut a diamond too shallow or too deep, and the light will escape through the bottom and the sides.
The more pure a diamond the more brilliant. Clarity refers to the number of imperfections in the diamond. These inclusions determine the rarity and value of the stone.