The lost-wax process is a fascinating process that makes it possible to create an impressive work of art from a simple silver bar. At BullionArt we are proud to use this traditional technique to produce our high-quality silver sculptures. In this article we will explain the lost-wax process in more detail and give you an insight into the fascinating process of transforming silver into art.
The original model and the silicone mould
Before the lost-wax process begins, the artist makes an original model. This model is frequently shaped from a solid material such as clay or another mouldable material. The artist can express their creative vision in this original model and create the forms and details they want. Once the original model is finished, a silicone mould is taken from it. This silicone mould serves as the pattern for making the wax models.
The casting process
The casting process begins with the wax model being embedded in a fire-resistant material, also known as the casting mould. To remove the wax model, the mould is heated so that the wax melts and runs out, which is what gives the process its name. What remains is a hollow mould representing the exact negative form of the original model.
Silver casting
Once the casting mould is prepared, molten silver is poured into it. The liquid silver fills the cavities of the mould and takes on the exact details of the original wax model. After the silver has cooled and solidified, the mould is removed and the silver sculpture emerges.
Challenges in casting fine silver
Casting fine silver presents a very particular challenge because of its specific properties. Unlike bronze or sterling silver, fine silver requires precise handling in order to achieve optimum results. The difficulties lie above all in two important aspects: the right casting temperature and avoiding the formation of cavities.
Fine silver has a very high melting temperature that has to be carefully controlled. Too low a temperature means the silver does not flow properly and the details of the model are not fully captured. Too high a temperature, on the other hand, can cause the silver to spatter uncontrollably or lead to unwanted inclusions and impurities.
Beyond that, fine silver is extremely sensitive to oxygen and tends to form cavities quickly. Cavities are voids or incompletely filled areas in the cast silver that can impair the appearance and the quality of the end product. To avoid this, it is decisive to control the casting environment carefully and to ensure that the silver is cast in an atmosphere rich in protective gas, in order to minimise contact with oxygen.
Mastering these challenges calls for experienced craftsmanship and specialist knowledge. At BullionArt we place the greatest importance on the expertise of our talented casters, who have years of experience in working with fine silver. Through precise temperature control and careful casting procedures we can ensure that every piece of fine silver art is of the highest quality and beauty.
Finishing and refinement
After the casting process comes the finishing and refinement of the silver sculpture. Here any burrs are removed and the surface is polished to achieve the desired shine and texture. The silver sculpture can additionally be decorated or patinated using various techniques in order to give it a unique and individual character. Finally the silver sculpture is numbered and stamped.
