Diamonds are cut into a number of shapes, depending on the nature of the rough stone. The cut or make of a diamond will dramatically influence its fire and sparkle, for it is the cutter's skill that releases it beauty. It is the cut that enables a diamond to make the best use of light. If the cut of the diamond is too deep, some light escapes through the opposite side of the pavilion. If the cut is too shallow, light escapes through the pavilion before it can be reflected.
People often confuse cut with the shape of a diamond.
The shape is primarily a matter of personal preference and is only limited by the skill and imagination of the craftsman.