We have heard it, said it, sang it before: Diamonds are forever.

It is -most definitely- the most famous, desired and precious gemstone, but what do we really know about diamonds?

Diamond is a rare, naturally occurring mineral composed of pure carbon. It is the hardest natural material known, and is extremely resistant to heat, pressure, and chemical substances. However, contact with greasy substances like hand creams should be avoided, as they can fog it’s adamantine luster. A fogged diamond can always be cleaned by a professional and get reinstated to its initial glow. 

All diamonds are unique, due both to their natural formation and their processing. Therefore, all diamond rings should be accompanied by a certificate that states each diamond’s “identity” and distinguishes it from every other. Diamonds can vary in sizes, shapes, colours, clarity, and rarity. In each unique combination of these factors lies the beauty of finding the diamond that suits you best.

There is, however, a standardized method of assessing diamond quality, developed in the 1950s by the Gemological Institute of America, best known as "The 4Cs of Diamond Quality", and it’s referring to their:

Carat Weight,



and lastly Cut.

Carat Weight

A carat (ct) is the weight unit of precious stones (and therefore of diamonds) corresponding to 0.2 grams. As diamonds are cut in various geometric shapes, the more the carat weight of the cut diamond, the bigger it is. A larger sized diamond is much more rare and thus much more valuable. The value per carat is growing exponentially as both the weight and the size of the diamond get bigger for every carat. 

Diamonds of exactly the same weight can have very different values, due to differences in the other three factors of the 4 C’s.



Diamonds can be divided in two categories, depending their colour. 

In the first category, Colourless, belong all diamonds that range from completely colourless to slightly coloured, usually in light tints of yellow. Exceptionally White diamonds are rare, therefore, the closer to colourless the gemstone, the greater its rarity and its value. 

However, vivid-coloured diamonds can also be found in nature. They are called Fancy Coloured Diamonds and vary in hues including yellow, brown and even more rarely pink, red, blue, green, purple, black etc. The precise conditions for coloured diamonds to be created naturally, render them extremely rare. Therefore, in this category, the saturation and the intensity of the colour is what increases their value. 



The clarity of a diamond depends on the presence of inclusions (particles of foreign material within a gem), visible when under magnification x10.

More precisely as Flawless are considered the diamonds that appear completely clear and free of inclusions under x10 magnification. Depending on the size and quantity of inclusions, diamonds are categorised from Flawless to Imperfect. The clarity of a diamond is also a rarity factor, therefore diamonds with an absence of visible inclusions are more valuable. 



The quality of design and craftsmanship used in cutting a diamond can bring out the unique optical qualities that reflect light and create iridescence. It is a common misconception that as “Cut” we refer to the shape of the stone (Style of Cut* ), when in fact it constitutes an evaluation of the proportions, the symmetry, and the quality of the polishing of the processed gem. The cut is graded on a scale from Excellent to Poor. 

* Style of Cut 

The most popular kind of cut is called Brilliant and can be applied to various shapes. The most usual ones are: Round Brilliant Cut, Oval Brilliant Cut, Pear Brilliant Cut (tear shaped) etc. Of course, many other kinds of cut exist, such as the Step Cut, mostly applied in styles like the rounded rectangles and the Emerald Cut.

For most of the classic designs of the PRIGIPO RENDEZVOUS Special Occasion Rings collection, we choose Round Brilliant or Pear Brilliant Cut diamonds. Nevertheless, some of our most particular jewellery and our One Of A Kind designs also feature various Styles of Cut diamonds and other precious gems.