Gemstone clarity refers to the amount of inclusions (trace elements or particles of other minerals) within a gem that create a unique set of identifying marks. Inclusions will not necessarily affect the quality, and in certain circumstances can even add value to a colored gemstone.
It is important to judge clarity against the standard that applies to a particular gemstone type. Because of unique natural properties, certain colored stones, including aquamarine and topaz, typically have fewer inclusions. Emerald and ruby, on the other hand, have a higher rate of acceptable inclusions.