The late 17th century is characterized by the creation of diamonds whose facets meet a certain symmetry that makes stones shine fabulously well. The diamond dealer and Belgian mathematician Marcel Tolkowsky highlighted the proportions in the size of the diamond to maximize the brilliance and fire of the stone.
The transformation of a raw diamond into a unique jewel is made through 5 key steps that are splitting, sawing, polishing, faceting and brightening.
This is the step during which a notch is hollowed in the stone to divide the stone into two parts. It aims at giving the stone a suitable form for sawing or sizing in order to eliminate crystallization defects, ice, inclusions and dives. The stone cleaves into 4 different directions.
This phase consists of cutting a rough diamond into 2 pieces which can then be cut, as a cleavage. The only difference with cleavage is that it retains the tip of the stone. This method allows sharing a non-cleavable diamond crystallization plan and is exercised through different sawing machines.
This preliminary operation is to round the belt of the jewel before it is cut into facets and can design the sketch that the stone will have once it is cut.
Using a polishing machine, a single or two-axis one, is indispensable to achieve this task. A very hard and low quality diamond called "Sherp" polishes and rounds the edges of the stone that are rounded to create the conical shape of the cut stone.
This phase, which requires a lot of skill and experience, consists of creating the facets of the stone. A brilliant is carved by different people, among whom a cross-cutter, an 8/8 cutter and ultimately by a brightener.
Achieving facets is usually done using a manual machine, but a computer is now more and more used to view on a screen the various steps. The computer takes into account the inclusions to determine the maximum dimensions that can be taken from a raw diamond.
This process is performed on the set of faceting, but on a different zone. It aims at creating light which will shine through the diamond, touch facets and reflect. To do this, the stone is rubbed on a disc coated with an abrasive to completely polish.