Diamonds which have a cut which is ideal to very fine and with proper total depth percentage provide the greatest brilliance. The total depth percentage is a very important element of a diamond's proportions and it is greatly responsible for the amount of brilliance that a diamond displays.

Shallow or deep stones will not look good.

Too Shallow	Too Deep	Good

This is a relatively narrow range that has been proven to produce the best "brilliance" from the diamond. Brilliance is the light that is reflected back to the viewers eye. Flat and heavy cut diamonds will loose light through the bottom and sides of the diamond thus reflecting less light to the viewers eye.