The Light Performance describes the beauty of the diamond, determined by the way the light is reflected out of the diamond and returned to the viewer.
The diamond’s Light Performance is affected both from the diamond’s natural characteristics, its Clarity imperfections and its Color, and more so by the way it is cut.
The Cut is determined by the craftsmanship of the diamond polishers and has perhaps the most significant influence on the diamond’s Light Performance. If the diamond is cut too shallow the light “leaks” out the bottom of the diamond, not allowing it to be seen. If the diamond is cut too deep the light is lost altogether. An optimal cut diamond ensures that the light reflects out through the top of the diamond, allowing its full beauty to shine through.
The Clarity affects the amount of light returned back out of the diamond, depending on the size, type and location of the inclusions. The Color, usually in the lower grades, affects the hue of light returned.
The diamond has four Light Performance parameters, which describe the different effects that each light characteristic reveals in the diamond.
The intense bright light that shines from the diamond
The dramatic flashes that burst out of the diamond as it moves
The vivid colors of the rainbow that radiate from within the diamond
The equal distribution of light that reflects from the diamond