After cut, diamond color is considered the second most important characteristic when searching and buying a diamond. The color of a diamond refers to the tone and saturation of color, or the depth of color in a diamond.
The "Diamond color grading system" actually refers to a diamond's lack of color, by essence grading the whiteness of a diamond on the premise that the major color that has been materialized and discovered in diamonds for past eons is a "Pale yellow". This was the main reason why the diamond's color grade was based on the lack of color in diamonds.
It's been agreed upon between diamond merchants for thousands of years, that the more colorless a diamond is, the rarer and more valuable it should be because it appears white and brighter to the eye.
The fact that there weren't many "white diamonds" out there to begin with, didn't hurt the correct assumption that "White Diamonds" should yield higher prices in general either.
In our days the current "COLOR GRADE SCALE" classifies diamond color into 22 grades from letter grade D through letter grade Z. So a diamond color grade of D is the highest possible while Z is the lowest.
As a rule of thumb, what known as a "colorless diamond" will be a diamond with a color grade of "D", "E" and "F", and is considered by the diamond industry as a diamond with no discernible color.
While those diamonds with a "near-colorless" color grade of "G", "H" and "I" are judged and viewed as diamonds with little or no noticeable color to the unaided eye.
Because of the above, in the past 50 years or so, the diamond industry reached to the natural conclusion that diamonds color grades "D" through" J" are best suited for jewelry because they look colorless or nearly colorless.
The most widely used system for grading the diamond color is developed by GIA (Gemological Institute of America). The system uses alphabetic letters ranging from D to Z to identify diamond colors. In terms of price, D is the most expensive color while N-Z diamonds are the least expensive. As mentioned above, When shopping for a diamond, it is generally preferred to choose a diamond stone with the least amount of color possible.
Diamond Color Scale:
|D E F||Colorless Diamonds: Diamonds within the colorless range are the most rare and valuable. D/E color stones display virtually no color, whereas F colored diamonds will display a nearly undetected amount of color when viewed by a gemologist. D-F diamonds should set in white gold / platinum.|
|G H I J||Near Colorless: G-J diamonds are suitable for a platinum or white gold setting. I-J diamonds are more common than the higher grades as retail for half the price of a D diamond.|
|K L M||Faint Yellow: K-M diamonds(usually a yellow tint) is more easily detected by the naked eye. These grades of diamonds emit fire and beauty.|
|N - R||Very Light Yellow: Diamonds in the N-R color range have an easily seen yellow tint, but are much less expensive than higher grades.|
|S - Z||Light Yellow or Brown: S-Z diamonds have too much yellow color. Diamonds with more color than Z, or in other shades such as orange, pink, blue, etc. are referred as Fancy Colored Diamonds.|