When shopping for a diamond, it is generally preferred to have the least amount of color possible. Diamond color is divided into five broad categories:
Diamonds within the colorless range are the most rare and valuable of all the colors. D/E color stones display virtually no color, whereas F colored diamonds will display a nearly undetected amount of color when viewed face down by a gemologist.
Near Colorless (G-J)
Diamonds within the near colorless range appear colorless in the face up position, but do display a slight amount of color when viewed face down against a perfectly white background. This trace amount of color will be undetectable to an untrained eye once the diamond has been mounted. Near colorless diamonds offer a tremendous value for the money.
Diamonds within the faint color range appear very faint yellow face up and face down. When they are mounted, small stones look colorless, but large ones show a slight yellow tint.
Very Light (N-R)
Very light yellow. These diamonds will appear a very light yellow, face up and face down as well as when mounted.
S-Z diamonds are light yellow and they will show substantial color loose or mounted, face up or face down. Once a diamond goes beyond Z, the color will be graded as a fancy.
Understanding Fluorescence – How does it affect a diamond?
Some diamonds can display a visible light called fluorescence when exposed to an ultraviolet light source. This fluorescence will be measured as inert, faint, medium or strong. Blue fluorescence is most common, however diamonds can also fluorescence white, yellow, and orange (among other colors). Fluorescence usually has no effect on a diamonds appearance in regular light conditions. Strong blue fluorescence can make a yellow colored diamonds appear whiter, but in rare cases can cause a stone to appear milky or oily. This milky or oily effect is called an “over blue” and only applies to a small number of “strong” and “very strong” fluorescent stones.
Which Color Should you Choose?
Most people find it very difficult (if not impossible) to tell the difference from one color grade to another. The difference in price, however, can be significant. The purists at heart will always demand diamonds in the D-F range. By selecting diamonds in the G-I range, however, you can find a tremendous value while still achieving a “colorless” look. Shopping on a budget or trying to maximize the size of your stone? If so then “J color” diamonds are most affordable and still near colorless. You may also want to consider choosing a diamond with faint or medium fluorescence. Since these diamonds are discounted slightly in price you can often afford a higher color stone without paying the premium.