How do you evaluate a diamond?

A diamond is judged by 4 characteristics and all together define the value of the stone.

This is the “rule of 4 C”

Weight in carat

The carat is a unit of measure refering to weight of diamond. The word “carat” has origin as unit of natural weight: the seeds of carob tree. The diamonds were weighed like these seeds, until the system was unificated and one carat was established at 0,2 grams.

Colour of diamond

This parameter refer to the colour of diamond and it was classified with the letters going from D to Z, where D is the most high level of white but even the most expensive and Z is the lowest colour level, beyond this classification we talk about “fancy diamonds”

Clarity of diamond

Almost all diamonds has inner imperfections called “inclusions” that are observed and valuated with a lens with 10 enlargements. These inclusions determines the value of diamond. If the inclusions are small or very small, the value of diamond will be high, and if one diamond is internally pure, the price will be at level maximum. The clarity level are: IF or internally flawless, VVS1-2 inclusions very very small and difficult to see, VS1-2 inclusions very small, SI1-2 small inclusions, P1-2-3 inclusions that you can see even without lens. Generally if the inclusions aren’t visible without lens or if aren’t black, they don’t affect the beauty of diamonds, but certainly they modify the price of it.

Cut of diamond

Cut of diamonds is a very important parameter of valutation for value of it, infact more the cut will be better and more will increase the brightness and the ability to reflect light. Today this parameter is very important, less in the past because after some studies the experts understood that if a diamond is cut respecting some proportions will be very more bright.


Fluorescence is a characteristic found in almost 35% of natural diamonds. If we put a diamonds under UV lamp it can emit a fluorescence, generally of light blue color. This natural characteristic can be very slight (VS) until to strong or very strong. This is a natural characteristic that if it’s very slight or slight doesn’t affect the price or the “beauty” of diamond. If the fluorescence is strong or very strong the stone will be opaque, so the purchase of a diamond with this characyeristic won’t be reccomended.