The diamond color evaluation of most gem-quality diamonds is based on the absence of color. Different colored diamonds other than the traditional white are available in yellow, brown, pink, and blue . Still, presence of yellow tints is undesirable in traditional white stones - less the body color, higher will be the true color reflection, enhancing its value.
Here below is the scale for color determination in diamond:
While there are differences in color between D, E, and F diamonds, they can be detected only by a gemologist in side by side comparisons, and rarely by the untrained eye. D-F diamonds should only be set in white gold / platinum. Yellow gold reflects color, negating the diamond's colorless effect.
Contain color traces, ideally set in platinum/white gold
Beginning with K diamonds, color (usually a yellow tint) is more easily detected by the naked eye.Set in yellow gold, these warm colored diamonds appeal to some, and are an exceptional value
Easily detectable brown or yellow tint and are less expensive compare than higher grades
Color presence is too much for a white diamond
Color becomes much harder to detect once a stone is set in a ring and placed in an environment that contains color). For instance, an H color diamond may look as colorless as a D when set in a ring. Another factor that affects a diamonds's apparent color is the color of the mounting itself. Yellow gold makes slight amounts of yellow in a diamond less obvious, while white metal mountings make the color in yellow diamonds more apparent.
Color becomes more important as carat weight increases, because color is easier to perceive in a larger diamond.