Diamond Cuts

Diamond Cuts

When jewelers or graders judge the quality and value of diamonds, they take consider the diamond cuts to be one of the most important aspects of assessing value.  The way a diamond cut is primarily dependent upon the original shape of the rough stone.  Also, the location of the inclusions and flaws to for removal.  The preservation of the weight, and the popularity of certain shapes. As a consumer, it is important not to confuse a diamond's "cut" with its "shape." Shape refers only to the outward appearance of the diamond, and not how the diamond cut is faceted.

Ideal Diamond Cuts

When a diamond has a high-quality cut (ideal cut), incident light will enter the stone through the table and crown.  The light then travels toward the pavilion where it reflects from one side to the other.  And then bounces back out of the diamond's table toward the observer's eye.  This phenomenon is referred to as "light return" which affects a diamond's brightness, brilliance, and dispersion.  All the desirable qualities that are considered ideal diamond cuts.  And furthermore, increase the diamond’s value. Any light leakage caused by poor symmetry and/or cut proportions will adversely affect the quality of light return, resulting in a diamond of lesser value. Light that enters through the diamond and reaches the pavilion facets and then leaks out from the sides or bottom of the diamond rather than reflecting back to the eye through the table, resulting in less light reflected back to the eye. Less light reflected back to the eye means less "Brilliance," resulting in less desirable qualities in the diamond, and therefore a less expansive stone.

Math and Diamond Cuts

Due to the mathematics involved in light refraction.  A cut that does not have the proper proportions and symmetry (off-make) will have noticeably less brilliance. Common cutting problems can occur during the faceting process .  Especially when one incorrect facet angle can throw off the symmetry of the entire stone.  This can also result in the undesirable creation of extra facets beyond the required 58. These mistakes will significantly reduce the grade and therefore the value of the diamond. In the past, the "Cut" quality of the "4 Cs" was the most difficult part for a consumer to understand when selecting a good diamond because a G.I.A. or A.G.S. certificate did not show the important measurements influencing cut and did not provide a subjective ranking of how good the cut was. Only a trained eye could see the quality of a good cut. All of that has changed with the AGS Cut Grading system and GIA's new "Cut Grading System” which is used to predict light performance and is included in the certification of the diamond. Four Diamond C's Diamonds