Diamond Cut: Anatomy of a Round Brilliant

A perfectly cut diamond is hard to achieve but should always be something strive for. This is a good article on the Brilliant Cut Diamond the Gemological Institute of America the worlds authority on diamonds has offered this for the public. It is well written so that anyone can understand what goes into a cut diamond and apply this knowledge to purchasing gems for your jewelry designs. The more one reads and researches the better choices and be made and it will show in your jewelry designs. The cut of a gemstone is very important to the presentation of the gem in jewelry. The brilliant cut was developed to get maximum light to enter the stone and reflect the brilliance of the piece in at it’s best. I have even he used this brilliant cut on my sapphire designs because it looks so good. It uses more gem weight but displays the gem in a better light than a step cut.

billiantcutA specific set of terms is used to describe parts of a polished diamond. Each part of a diamond makes its own contribution to the diamond’s appearance. In the standard round brilliant, there are 57 or 58 facets. The table facet, usually the largest facet on the diamond, helps gather light from above and either reflects it back to the observer or directs it into the diamond’s interior. The crown facets, consisting of 8 bezels, 8 stars, and 16 upper halves, gather and disperse light to create brightness, fire, and a scintillating pattern of light and dark. The pavilion facets, consisting of 16 lower halves, 8 mains, and an optional culet, reflect the light back through the crown to the viewer’s eye. All of these facets work together creating each diamond’s unique appearance.
Average Girdle Diameter

The diameter of a round diamond is the distance from one girdle edge to the opposite girdle edge, straight through the center. Because even well-cut round diamonds are never perfectly round, the diameter is measured in several places, recording the minimum (smallest) and maximum (largest) measurements.
The average girdle diameter is a calculated value obtained by the following formula, which is then reported to the nearest hundredth of a millimeter (0.01 mm):
Average girdle diameter = (minimum diameter + maximum diameter) ÷ 2
This proportion is used in calculating certain percentages such as table size, total depth, crown height, and pavilion depth. READ MORE…

About Rob

I have been designing military coins and jewelry for nearly 40 years now.