The color appearance of a gem is the result of a combination of these three attributes. The Gemological Institute of America (GIA) system for color grading colored diamonds uses 27 hues, which are indicated on the hue circle chart. Some of these 27 hue names include modifiers, such as purplish pink.

A modifier in a hue name (such as yellowish green or orangy yellow) does not mean a lack of purity in the color.