How Lost-Wax Casting Connects Modern Jewellers to Ancient Egypt

The pendant you commission from a contemporary jeweller in Hatton Garden is produced by essentially the same process Egyptian goldsmiths used for Tutankhamun. Lost-wax casting, in which a wax model is encased in a mould, the wax melted out, and molten metal poured into the cavity, has remained the dominant method of precision metal casting for over five thousand years.

The process begins with carving or modelling a wax original. Modern jewellers use injection wax or 3D-printed wax from specialised printers. The wax model is an exact replica of the desired piece, complete with all surface detail and dimensional accuracy needed for the final metal object.

Investment involves attaching the wax to a tree structure creating channels for metal flow and gas escape. The tree is surrounded with investment plaster capturing every surface detail. Once set, the flask enters a kiln where wax melts and drains, leaving a perfect negative cavity.

Casting requires precise temperature coordination. Gold is typically poured at around one thousand degrees Celsius into a mould preheated to five hundred degrees. Centrifugal or vacuum casting forces metal into fine details gravity alone cannot fill, ensuring complete reproduction of the original wax.

After cooling, investment is broken away revealing the raw casting still attached to its metal tree. The casting is cut free, cleaned in acid pickle, and finished by filing, sanding, and polishing. Setting stones and applying surface textures transform the raw casting into completed jewellery.

After cooling, the investment plaster is broken away revealing the raw casting still attached to its metal tree of channels. The casting is cut free, cleaned in acid pickle, and finished by filing, sanding, and polishing to the desired surface quality. Setting stones and applying surface textures then transform the raw casting into a completed piece of jewellery. Learn more at https://www.ganoksin.com