At the diamond assorting office of Rasiklal and Sons, professional diamond assorting personnel sort and grade the stones on the basis of colour, clarity, shape and size, in accordance with stringent pre-defined standards. The diamonds are usually gauged into different lengths, as in the case of princess cuts and tapered baguettes. Round diamonds are sifted into different sizes with the help of a sieve.
The Design Process
The design team collectively develops multiple new styles every month, all in keeping with the prevalent trends and designs in vogue. Every design is created with the help of advanced software technology. Careful attention is given to measurements, total diamond weights and metal thickness. A three-dimensional view of every design is created before it is approved for model making.
The Model-Making Process
This is the single most important process in manufacturing, as even a small lapse in quality will magnify itself in every consecutive stage. While traditionally models were made directly in silver, most model makers now use wax as an alternative, which is then cast in silver. Each model maker meticulously follows the designs and its measurements to the last decimal, approximations are not tolerated. Great efforts are made to ensure that each model is no less than a masterpiece in itself.
Creation of wax replicas of the master model
In this stage, an impression of the master model is formed in rubber by sandwiching it between sheets of rubber and vulcanizing at a temp of 310 to 350 Fahrenheit. The rubber mould is skillfully sliced open so as to leave behind the perfect cavity of the model.
The rubber mould is then inserted into a wax-injecting machine that shoots out wax in a molten state at a pre-set temperature and pressure. The wax cools inside the rubber within a few seconds, solidifies and assumes the shape of the cavity. This process is known as wax shooting. The wax replica is carefully extracted from the rubber mould.
Depending on the design, the diamonds may be set in the wax replica itself before the model is cast in gold. Alternatively, for larger stones and more intricate designs involving pavé work, bead setting, the stones are mounted only after the model is cast in gold. This ensures a more exquisite finish, with greater attention to proportions and symmetry.
The Casting Process
The wax replicas are affixed to the central rod in a symmetrical fashion to give the resemblance of a tree. The wax tree is then fitted into a flask and the investment mixture consisting of water and a gypsum-based powder is poured onto it. As this plaster hardens, the wax tree is set firmly in place. The flask is then placed in a furnace where the wax melts creating a cavity into which the molten gold flows filling up every crevice. Once the gold has been cast, the flask is cooled by slowly quenching it in water. The plaster is then removed under a water jets, finally revealing the gold trees. Each gold model is deftly cut from the tree.
The Finishing Touches
At this stage, small porosities or waviness in the metal surface would be smoothened out. Soldering of ear posts and bracelet links takes place. With the help of brushes and a polishing wheel, each jewellery item is then polished to achieve the required finish. Some pieces are plated with rhodium to render the metal more lustrous and the diamonds more brilliant.
Between each process described above, the items of jewellery are passed through stringent quality control procedures. We have multiple stringent quality checks for each and every piece. Quality control personnel are professionally trained to meticulously examine each item, in accordance with pre-determined parameters.