There are three different criteria used to determine a fancy color diamond’s color and intensity:
The primary and secondary colors determine the tone of the diamond’s color. The strength of the color is defined by its level of intensity. As a general rule of thumb, a fancy color diamond becomes more valuable as the color intensity increases. The classifications for fancy color diamonds are as follows: faint, very light, light, fancy light, fancy, fancy intense, fancy vivid/fancy deep/fancy dark.