Diamonds are cut according to an exact mathematical formula. A finished diamond has 58 "facets," which are the small, flat polished planes cut into a diamond, so that the maximum amount of light is reflected back to the viewer's eye.This reflection is called "brilliance," and is extremely important in evaluating the quality of a diamond. The widest circumference of a
diamond is the "girdle." Above the girdle are 32 facets plus the "table," the largest and topmost facet. Below the girdle there are 24 facets plus the "culet," or point. Cut also deals with the shape of the diamond. Traditional shapes are round, emerald, marquise, pear, oval and heart.