Deep in the earth, when a diamond was being formed out of carbon, certain chemicals may have been drawn into the mix. The result is an added tinge of color in the transparent stone. Most common in diamonds is a degree of brown or yellow color, but diamonds have been found in all the colors of the rainbow.
When jewelers talk about the "fine color" of a diamond, what they really want you to notice is how little visible color the stone has. Colorless, or icy white, diamonds are the most prized and most expensive. The slightly colored diamonds are less valuable than the perfectly white or boldly colored red, yellow, and blue "fancies." The 45.52 carat Hope Diamond, on display at the Smithsonian, is remarkable in part for its prized cornflower blue color.
Diamonds are graded according to the GIA color chart.
|GIA color grade
||What is it called
||What you see
||Stone looks absolutely clear, with no hint of color to the eye in color grading or mounted
||Some color tint is visible during grading. Mounted in a setting, stone appears colorless
||Yellow or grayish tint is obvious during color grading. Mounted, this stone still shows a tint of color
||Obvious yellow or grayish color
||Bright, remarkable color - usually blue, pink, yellow
Private companies once used their own grading systems and called diamond colors AA+, AB, 1+, etc. The GIA (Gemological Institute of America) - an independent, non-commercial association - wanted to create a standard chart that couldn't be compared or confused with others. Thus, the perfectly colorless diamond is now given a color rating of D. Any company that tries to sell you a diamond they rate as "A+" in color is probably up to no good.