This is one on the most important characteristics of any diamond because it can be seen from a distance.

The G.I.A. color grading system starts at the letter "D". This is to avoid confusion with other homemade systems that usually start with the letter "A" or "AAA". These homemade systems are usually designed to sell stones, and the G.I.A. system is designed to tell the color of the stone.

The grades of D, E and F are considered to be absolutely COLORLESS in and out of the laboratory. The next color range is NEAR COLORLESS, and it consists of the colors G, H, I and J. Stones in these grades will "face-up" colorless. Slight traces of color will not be apparent in the mounted stones other the the J color and then only to the trained eye. K, L, and M are in the FAINT YELLOW range. Small stones in this range will "face-up" colorless when mounted, but larger stones will be slightly tinted. Colors N through Z will display a yellowish tint, even to the untrained eye.

A "Z+" color is considered FANCY. A fancy will have more value than an obviously yellow diamond which may look like a Fancy. Remember it is important that clients get the true value for their dollar, so they should make sure it is a "Z+" Fancy. Also, diamonds can be treated to achieve Fancy colors. A natural Fancy color is much more valuable than a treated Fancy color. Therefore, if a client is interested in a Fancy, they should make sure to get a G.I.A. Certificate to prove that it is a "Z+" and that it is a natural color.

Color grading must be done in an absolute white environment with certified "Master" stones of a known color. The unknown diamond is moved between the "Master" stones until the true color is discovered. The human eye is the best judge of color, and women can see color better than men. However, the human eye is easily deceived outside of a white environment. When a faint yellow diamond is mounted in a heavy yellow gold mounting, or if it is shown on a brown pad, it will fool the human eye and look whiter.