Some diamonds are split in two or more pieces.
The intention is twofold:
-either to give the diamond a suitable form or,
-either to eliminate impurities and / or to eliminate irregularities.
The cleaving is done according to the four cleaving directions or crystallographic faces of the diamond crystal. This requires first a notch (kerf) to be made. Previously this was done manually with another piece of diamond. Currently, the laser executes this operation entirely .
Subsequently, a cleaving knife is placed in the notch. A short hammered stroke esures the diamond splitting.
The advantage of lasercleaving is the better shape of the notch and that will make the cleave direction more exact. The notch is more rectilinear and has a V-shape in stead of a U-shape. The notch becomes smaller, but the depth remains unchanged. Making the notch goes faster with the laser. Eventually the cleaving can be done with a very fine blade in stead of a steel splitting knife.