Tiny particles of carbon and other elements, that have not been crystallized, are included in almost every diamond. In most diamonds, these traces are not visible with naked eye and they can identified with a 10x magnifying achromat-aplanat loupe.
These inclusion determine the identity of each precious stone and its uniqueness.
The smaller the number or inclusions the better the clarity of a diamond and consequently its rarity and value.
This is why you should be aware of the clarity grading scale before you decide to buy your diamond.
IDENTIFIED BY 10X MAGNIFICATION LOUPE