A total of 31 hues can be seen in all the gemstones, and they can appear in various tones. These can be particularly seen in fancy colored diamond design rings. Below are a few properties regarding the tone of colored gemstones.       The most commonly found tones are between a very light category and a very dark category. Note that the most valuable and sought-after gemstones come under the medium or medium dark category of gemstones. Generally, the different tones appear rather empty without any hue. It takes a high level of expertise, patience, and practice to superimpose hues on to each of the tones, and only that will give you a tone reading. Another fact that you need to consider is that every gem species is different in terms of their inherent tone ranges. To understand this better, let us consider the case of a pyrope garnet and an aquamarine. Both have a tone reading of 6. So you may be compelled to consider them the same in terms of color. However, the depth of color depends on the deepest shade of aquamarine you can find and the lightest shade of pyrope. Hence, the aquamarine would be called ‘very dark’ and the pyrope would be considered ‘very light’ even though they both belong to tone 6.