Ideal Cut

Many years ago, the "ideal" proportions of a round brilliant cut were mathematically computed. While these proportions will generate a diamond with not only the maximum reflection of light, they also render the ideal balance of brilliance (reflected white light) and dispersion (refracted spectral colors). Unfortunately, the maximum potential weight recovery from the rough is sacrificed. Modern day diamond cutters attempt to balance these factors and will most frequently allow popular weight categories that are targeted as well as increased yield to direct their cutting decisions.

A diamond which has been cut too shallow will not only reflect less light, but the lessening of the angles of the pavilion facets will also make the stone "window" or show a see through effect. This appears to the eye as if there were dead space instead of sparkle. These diamonds will also often show an internal reflection of the top of the stone in the bottom, which resembles a dark circle or "fish-eye".

A diamond that has been cut too deep will generally appear dark through the center. This occurs because the light is "leaking" through the back of the stone instead of reflecting back to the eye through the top. Add to this, the fact that the diameter of the stone, or it's apparent size, is minimized and you have a smaller facing stone than it's weight would usually render.

The Ideal Cut, which is illustrated below requires exact placement of facets at exact angles relative to one another. They are generally available to a discerning buyer at a premium over all other diamonds in their class.

A Premium Cut diamond demonstrates subtle variations from the Ideal Cut. Although these differences do affect the reflection of light, a Premium Cut still achieves a harmonious balance between it's proportions and the display of brilliance and dispersion.