The existence of imperfections in a diamond
All but the finest diamonds have tiny imperfections or inclusions, often not visible to the naked eye. Inclusions are natural minerals or fractures appearing whilst the diamond is being formed. These may appear like tiny crystals, clouds or feathers.
Clarity refers to the visibility, number and size of inclusions in a diamond. Diamonds with greater clarity have fewer inclusions, and as a result are more brilliant and valuable. Where the inclusions are positioned on the diamond can also affect its value.
The clarity of a diamond is graded on a scale established by the Gemological Institute of America (GIA). The clarity scale ranges from F (flawless) to I (included), based on the visibility of inclusions at a magnification of 10x.
Diamonds with a clarity grade of F or IF have no imperfections and are extremely rare. Diamonds with VVS1 and VVS2 grades have very very small inclusions which are difficult to see under 10x magnification. These are excellent quality diamonds and are more valuable. Diamonds with lower clarity grading have inclusions which can be seen under 10x magnification and may also visible to the naked eye.