A diamond's color, graded on a scale from D (colorless) to Z (light yellow), refers to the presence or absence of color in a diamond. As a rule, the closer a diamond is to colorless, the more valuable and beautiful it is. Truly colorless stones, graded D, are extremely rare and very valuable.

Many diamonds appear to be colorless, or white, although when comparing diamonds side by side you may see that they actually have subtle yellow or brown tones. Diamonds were formed billions of years ago under intense heat and pressure, and traces of other elements may have been incorporated into their atomic structure accounting for the variances in color. A single change in color grade can significantly affect a diamond's value. Generally, the presence of color makes a diamond less rare, as well as less valuable. However, "gancy" diamonds, which come in vibrant colors such as red, green and blue, are highly prized and extremely valuable.

Color Grading Scale
D-F: Colorless, perfect or almost perfect color.
G-J: Near colorless, good to very good color. This diamond may "face up" colorless when mounted.
K-M: Light but noticeable yellow or brown tint. May "face up" near colorless when mounted, especially when mounted in yellow gold.