Refers to the angles and proportions of a diamond. Based on scientific formulas, a well cut diamond will internally reflectlight from one mirror-like facet to another and disperse and reflect it through the top of the stone. This results in a display of brilliance and fire, thereby placing well-cut diamonds higher on the diamond quality pyramid than deep or shallow cut diamonds.
Diamonds that are cut too deep or shallow will lose or leak light through the side or bottom, resulting in less brilliance and value.
