In the past, only raw, untreated stones were used in diamond jewellery, and people did not know how to work with this mineral. Diamonds began to be cut for the first time in the 15th century. The most common cut is currently the brilliant cut.
The untreated and unpolished diamond looks like a piece of glass, so in the past, jewellery with uncut diamonds was not so sparkling and beautiful as it is today. At the turn of the 14th and 15th centuries, Lodewijck van Bercken from Belgium found the way the rough diamond can be cut - only by another diamond. Cutting a facet creates a masterpiece, a beautiful, glittering diamond.
Did you know that diamond processing usually results in the loss of half the weight of the raw stone?
The most commonly used abrasive is the round diamond. A typical round diamond has a total of 57 faces: a table (large facet in the middle), 32 facets on the crown (top of the diamond), and 24 faces in the pavilion (bottom of the diamond tipped). When grinding, it loses more than half of its original weight.
Diamonds nowadays are processed using modern methods, such as laser cutting and stone shaping. For the final stage of diamond trimming and its grinding into a gorgeous, shining jewel, however, human work and skill remain irreplaceable.
Processing diamonds underneath
Each stone to be machined is first labeled with a cutting plane laser. Each diamond is unique, depending primarily on the shape and quality of the raw material.
The rough diamond is divided into two or more parts with splitting. Splitting occurs with one shot in a certain direction. The stone is fastened to the wooden holder, a second sharp diamond is seated against it and a notch is made into the workpiece.
The diamond is attached to the copper head using a special mixture of gypsum and limestone. Once the mixture hardens, the head is clamped onto the cutting machine and the stone is cut with an extremely thin disc. The disc is smeared with oil and diamond dust, reaching a frequency of 10 to 15 thousand revolutions per minute. Cutting is best done at a rate of about one millimeter per hour, which can take a few weeks for large stones.
The diamond gets its future shape by rounding the split or cut stone. The diamond is attached to the lathe and the stone is rounded, the stone gaining its famous circular shape.
Sanding on the surface of the diamond creates beads, faces of different shapes that reflect light. The diamond is attached to special grinding machine pliers and is set at a precise angle to the grinding wheel - this disc is made of steel and is smeared with diamond dust oil.
Madehow.com. (2016). How diamond is made - material, history, used, processing, parts, components, structure, industry, history. [Online] Available at: http://www.madehow.com/Volume-2/Diamond.html [Accessed 6 Dec. 2016].
Academic.emporia.edu. (2016). Diamond Extraction Methods. [Online] Available at: http://academic.emporia.edu/abersusa/go336/ringler/diamondmining.htm [Accessed 6 Dec. 2016].