Diamond clarity refers to the presence of certain characteristics on (blemishes) and within (inclusions) the stone. As you would expect, diamonds with no or few blemishes and inclusions command a higher price because they are rarer - most diamonds are not flawless in appearance.
Diamond blemishes include scratches, pits and chips, which often occur during the cutting process. Inclusions on the other hand are naturally occurring - when diamonds are formed deep in the earth under extreme pressure and heat, imperfections in the crystal structure can lead to natural birthmarks and irregularities.
Evaluating diamond clarity involves a process that will determine the number, size, relief, nature, and position of its blemishes and inclusions, along with how these affect the overall appearance of the stone.