Light Performance Theory

Light Performance Theory measures how well cut a diamond is, and how that diamond reflects and returns light. When light enters, it is either reflected or leaked off the diamond. The reflection of light makes the diamond shine and proves its brilliance, whereas the leaked light goes unnoticed. Stone clarity also plays some role in this, but the cut is mostly responsible for the reflection of light. The light performance test is done under various lighting conditions. Similar to the Gemex Analyzer certification (which is basically a light performance test as well), the diamonds are judged based on brilliance, fire, and sparkle.