diamonds used in jewelry are nearly colorless with tints of yellow or brown.
Color grades are determined by comparing each diamond to a master set.
Each letter grade represents a range of color and is a measure of how noticeable a color is.
Because diamonds form under tremendous heat and pressure, it is extremely rare to find a diamond that lacks any internal and external characteristics. This characteristic are a byproduct of its formation and help gemologists separate natural diamonds from synthetics and simulates, and identify individual stones.
The cut scale ranges from excellent to poor, and provides a cut quality grade for standard round brilliant diamonds that fall in the D to Z color range. The result is a magnificent display of three attributes. Brightness is the combination of all white light reflection from the surface and interior of a diamond. Fire describes the "flares" of color emitted from a diamond. Dispersion describes the flashes of light you see when the diamond, the light, or the observer moves.
A polished diamond's proportions affect its light performance, which in turn affects its beauty and overall appeal. Diamonds with fine proportions, symmetry, and polish optimize their interaction with light and have increased brightness, fire, and dispersion.
One carat equals 200 milligrams in weight. For diamonds under one carat, each carat is divided into 100 points - similar to pennies in a dollar. 0.75 ct. = 75 points, 1/2 ct. = 50 points.
Birthstone color chart