Diamond Colors
Grading Diamond Colors
When looking to buy or sell diamonds, you need to know about the Four C’s. The Four C’s of diamonds are diamond clarity, diamond carat weight, diamond cut and diamond colors. Diamonds are not actually colorless. They actually have colors.
White diamonds are the colorless diamonds. All other diamond colors are judged according to the white diamond. There are set guidelines to use when judging or grading diamonds. The Gemological Institute of America or GIA devised the set of guidelines for grading diamond colors. Control stones (preselected gems representing specific colors) are used as the basis for comparing the diamond colors.
When grading diamond colors, it is important that the diamonds are not yet set. Setting the diamonds into metals affects the diamond colors. Grading begins by placing the diamonds on the table pavilion-up. A 10x loupe is used to view the diamonds. The GIA grading system uses the letters D to Z in identifying how much color is in every diamond. Totally colorless diamonds are given the letter D. The D rating is very, very rare.
Diamond Colors
If you have colorless diamonds, diamonds that are yellow and diamonds that are yellowish brown, the following color grading below applies. However, for fancy colored diamonds, another grading system is used.
- Colorless diamonds: D, E, F
- Nearly colorless diamonds: G, H, I, J
- Faintly tinted or usually yellow diamonds: K, L, M
- Lightly tinted (enough for the tint to be seen by the naked eye), usually yellow diamonds: N, O, P, Q, R
- Tinted (tint can be seen by the naked eye): S, T, U, V, W, X, Y, Z
Fluorescence can affect diamond colors according to the GIA. Ultraviolet radiation can change diamond colors when the diamond is exposed to this type of radiation. High pressure/high temperature processing can also affect the diamond’s colors. And, as mentioned earlier, setting diamonds in metal can affect the colors of the diamonds.
Diamond colors affect the price of diamonds. Make sure you not only have intimate knowledge of diamond colors but also of diamond clarity, carat and cut so you are able to pick the right stones or know when you are buying the diamonds at the right prices.