What makes diamonds stand out beyond any other precious gemstone is their fire and brilliance. While nature determines the color and clarity of a stone, the cut is dependent solely upon the skill of the cutter.

The cut of a diamond is what determines how the light that enters the diamond is reflected and therfore how much fire and brilliance the diamond will exude. A diamond that is cut too shallow with respect to its width will allow too much light to pass straight through the diamond, leaving little light to reflect. Such a diamond can sometimes appear dull and lacking in brilliance. Conversely, a diamond cut too deeply will allow light to escape from the sides of the diamond.

The depth and table measurements, which are used to determine how good the cut is, are given in percentages of the girdle (the widest part of the diamond). So, if a diamond's girdle measures 10 millimeters, the table measures 5.6 mm, and the total depth measurement is 6.25 mm, it would have a table of 56% and a depth of 62.5%.

In order to cut a stone to ideal proportions, much of the rough diamond is sacrificed, leaving a stone with a smaller carat weight.