The description of inclusions and blemishes.
Clarity is quite often misunderstood by sales people and therefore by customers. Clarity grades are used to describe the diamonds internal inclusions and blemishes. These grades are based on several determining factors including size, colour and position. Despite the fact that clarity is always determined by using 10x magnification, above the “Included” grades (see below), the average human eye will not be able to see any imperfections to the naked eye.
IF - Internally Flawless
VVS1, VVS2 - Very Very Slightly Included.
VS1, VS2 - Very Slightly Included.
SI1, SI2 - Slightly Included.
I1, I2, and I3 - Included.