The quality and value of a diamond is measured by four characteristics known as the 4 C's. The 4C's are the diamond's Cut, Colour, Clarity and Carat weight. The quality of a diamond is measured by its colour, cut, and clarity. The carat weight measures the size of the diamond.


A diamond's colour is one of the most important factors in determining its value.
For white diamonds - the closer a white diamond is to being absolutely colourless, the more valuable it is.

　

　

 　
　 A Pic of Swiss Simulate Diamond

Even experts can't tell the difference just by the look

 Just like colour, clarity is categorised using an international grading scale. The categories of clarity are based upon the number, size and position of the inclusions within the diamond to be graded. Gradings range from flawless, and internally flawless, through very small and small inclusions, to imperfect.