All over the world, also following theconference organized by De Beers in 1976 in Lausanne, the "4Cs"classification rule applies to diamonds: carat, cut, colour, clarity. The"4Cs" provide a precise and systematic language in English that allows everyone to compare and evaluate diamonds.
The value of a diamond is based on the realpossibility of classifying it according to this rule. The best colour, the bestcut, the best purity for the same weight make a Diamond absolutely rare whoseabsolute value is then gradually modified if the characteristics become worse.So rarity and value are directly related. The rarer the feature, the moreprecious the diamond is.
The final value of a diamond is formedfollowing the characteristics dictated by the "4Cs":
For example, if a customer tends to buy adiamond favouring the eye and therefore larger than that of the best absolutequality, he will be able to balance the greater cost dictated by the weight,choosing less rare characteristics, although without disfiguring its beauty, itwill make it with a final cost within the limits established by him.
It is important to remember that while eachdiamond can be described by a certification issued by a recognized GemmologicalInstitution, its beauty will be represented by the observation with the nakedeye capable of enhancing its brilliance represented by the facets of the cutchosen among the different existing types.