When a diamond has been perfectly cut, the diamond’s ability to reflect and refract light is greatly enhanced (in what consumers see as the “sparkle” of a diamond). In order to best understand the way that light moves through diamond crystals, modern diamond cutters have established a specific set of proportions and angles that are known to harness the diamond’s internal brilliance and to show it in its best light. Therefore, a diamond’s cut grade is actually a combination of three different types of reflection of light: brilliance, dispersion and scintillation.