For Seller

By: Tom Shofner

Diamond colors can vary widely from colorless, (also called white), to the fancy colored diamonds, which is a term used to describe basically any desirable color of diamond other than white.

Fancy colored diamonds can be found in brown, yellow, blue, green, pink, and red, and occur in various degrees of hue, saturation, and intensity. Colored diamonds can be classified into two categories: as untreated, unenhanced, naturally occurring diamonds, or as treated/enhanced colored diamonds.

The color grading system described here was developed by the Gemological Institute of America, (GIA). It is the standard grading system used in the U.S. and, for the most part, around the world. Diamond color grades are represented by letter grades starting at "D", which is completely colorless, the absolute best colorless grade, and goes all the way to "Z", which would be a very obviously brown, or brownish-yellow color. After "Z", the fancy color grading system is used. Typically, for white diamonds you will only see grades "D" through "M" or possibly "N".

Grades are grouped in three major groups:

Colorless — D, E, and F;

Near-colorless — G, H, I, and J;

Faint yellow — K, L, and M;

Very light yellow — N - R;

Light yellow — S - Z.

Diamonds are graded with the table side down"¦this means upside down to the way they are mounted. Thus, when a diamond is mounted in a setting, this usually makes accurate color grading impossible using a color master set. Newer technologies now make it possible to color grade a diamond while mounted, but these instruments are very expensive and not widespread.

Diamonds presented for grading, which are mounted, will only be a "best estimate". Color master-sets are typically used to color grade diamonds. These master-sets are diamonds, or CZ’s that have been compared against a master-master set, and can then be used to compare to other stones. The GIA maintains such a master-master set of diamonds at the Gem Trade Lab in Carlsbad, California. Other means of color grading include newer electronic technology to grade the stone automatically.

Color preferences vary and are individual in nature. Diamonds mounted in platinum may require a better color grade to ensure the color tint does not show against the pure white of the metal. Color grades of G through J can be mounted in white gold, which has a slight yellowish tint to it which can tend to hide the lower color grade of the stone. Another factor that can affect the way a stone looks is the quality of the cut. A very good quality cut can help mask the color in stones that have a yellow or brown tint to them. By paying a little more to get a stone with a better cut, you can save on the color side of costs by getting a lower color grade without sacrificing the look of the diamond. Nicer cut diamonds, of poorer color grades can look much whiter than the color grade would suggest since the quality cut allows less light leakage and thus more white light is directed out of the top of the stone "bleaching out" the natural body color

Tom Shofner is a certified gemologist and owns Palmetto Gems in Columbia, SC His website is http://www.palmettogems.com