C1: Cut
What makes your diamonds stand out beyond any other precious gemstone? Your diamond will shine with intense fire and brilliance. Nature determines the color and clarity of any diamond, but the cut of your diamond is dependent solely upon the skill of the diamond craftsman.
The cut of a diamond determines how light enters the stone and is refracted. The intensity of the fire and brilliance your diamond will exude is determined solely thought the diamond cutters skill. When a diamond is cut too shallow with respect to its width it will allow too much light to pass straight through the diamond, leaving little light to reflect. Such a diamond will appear dull and lacking in brilliance. Conversely, a diamond cut too deeply will allow light to escape from the sides of the diamond, also appearing dull and lacking brilliance.
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). If the girdle of your diamond measures 10 millimeters, the table measures 5.6 mm, and the total depth measurement is 6.25 mm, your diamond would have a table of 56% and a depth of 62.5%. The percentages which yield an ideal cut vary from shape to shape based on the size of the diamond.
Depth & Table Measurements

In order to cut a stone to ideal proportions, much of the rough diamond is sacrificed, leaving a stone with a smaller carat weight. Diamond cutters sacrifice ideal proportions to derive a larger, more profitable stone. Industry standard valuation of diamonds (Rapaport) does not take into account a diamond’s proportions, thus a larger stone with fair proportions will be worth more than the smaller one with good proportions to a diamond cutter (color and clarity being equal). Consequently, ideal cut stones are very rare and hard for wholesalers and retailers to find, and as the consumer, you will see that these rare stones are priced accordingly.
Ideal Cut
When a Diamond is an Ideal Cut you have a stone with a very rare cut. The Ideal Cut Diamond will reflect nearly all of the natural light that enters. The Ideal Cut Diamond creates the maximum fire and brilliance by refracting almost all light with brilliance and fire.
Premium Cut
When a Diamond is a Premium Cut it reflects almost as much light as the Ideal Cut, but is slightly less brilliant. A Premium Cut Diamond is a very solid investment and a magnificent stone.
Good Cut
When a Diamond is a Good Cut it will reflect most light that enters the diamond, but not as brilliantly as a Premium Cut diamond. This lowers your cost to acquire and is a good investment.
Fair Cut
When a Diamond is a Fair Cut you still get a quality diamond, but a Fair Cut diamond will not be as brilliant as a good cut.
Poor Cut
Shallow Cut:
When a Diamond is a Shallow Cut the light is lost through the sides, causing the diamond to lack fire and brilliance.
Deep Cut:
When a Diamond is a Deep Cut, the light passes through the diamond, causing it to appear dark and dull.