CLARITY

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 it's cost.

One unique advantage of the Ideal Cut is that it's sparkle can mask otherwise noticeable inclusions

No inclusions visible (by an expert)
under 10x magnification.
(FL = Flawless)
(IF = Internally Flawless)

Minute--extremely difficult to find under 10x.
(VVS = very very slight inclusions.)

Minor--difficult to find under 10x.
(VS = very slight inclusions>)

Noticeable, relatively easy to find under 10x.
(SI = small inclusions.)

Obvious under 10x--Just visible to the naked eye.
(I = imperfect.)