he diamond prices are determined on the basis of what are the odds "Rapaport". Rapaport prices are generally accepted and are used in all commercial, certified diamonds, among professionals and traders worldwide.

Prices Rapaport rappresentono prices of diamonds found in the New York Stock Exchange, are not really a sales list, but a guide in pricing between professionals. These prices within the Rapaport sheets are expressed in US dollars.

The Rapaport price lists take account of 4C for evaluation of diamonds, while the quality of the cut, proportions, finishing and fluorescence (as well as the institution that issued the certificate) affect% discount applied to the list.

It should be noted that for the same color, clarity and cut the cost of a stone does not vary linearly with its weight (carat), but this takes place only within predefined ranges (eg .: 0.50 to 0.69 0 , 70 to 0.89 from 0.90 to 0.99 1.00 to 1.49); consequently the cost of a stone from 1 carat is not, for the same of the other features, equal to the double of a stone of 0.50 carats, but equal to about six times.