Grading the color of a stone is another difficult factor to understand without proper training. However, the scale is very easy to understand once you know it. The color range of a diamond starts at D through Z. After Z you start getting into the Fancy Color system, which is a whole different animal. The D-F range is considered colorless or white. This is the most expensive color in diamonds. As important as color is, it’s also important to consider that when a diamond is mounted in a ring, the color tends to fade. For example, a diamond with F color and a diamond of H color may look different loose, however when mounted they effectively look the same!