Practically all diamonds contain naturally occurring internal characteristics called inclusions. The size, nature, location and amount of inclusions determine a diamond's clarity grade and affect its cost.

	FL - IF No inclusions visible (by an expert) under 10x magnification. (FL = Flawless, IF = Internally Flawless.)
	VVS1 - VVS2 Minute - extremely difficult to find under 10x. (VVS = Very, very slight inclusions.)
	VS1 - VS2 Minor - difficult to find under 10x. (VS = Very slight inclusions.)
	SI1 - SI2 Noticeable - relatively easy to find under 10x. (SI = slight inclusions).
	I1 - I2 Obvious under 10x - Just visible to the naked eye. (I = Imperfect).