Lost-wax casting is an ancient technique for replicating an object in metal. In casting a hollow piece, the interior of a mold is coated with layers of wax and the core of the wax shell is filled with heat resistant material. When heated, the wax drains off to leave a cavity that will later be filled with molten metal. A solid piece can be cast by encasing a solid wax model to form a casting mold. The process is also known in art as cire perdue and in industry as investment casting.
Examples of lost-wax casting have been found in multiple cultures dating to 3, 000 BC. The technique itself has essentially remained the same over the years. The components used have evolved from the original bronze, beeswax and pottery clay to modern alloys and synthetic materials.
Typically, the procedure begins with the creation of a model either by hand or by injection into molds taken of an original design. Wax or a similarly workable material is usually used. A mold of the result suitable for metal casting is then made. The interior of the mold is the exact negative image of the model. This allows any detail that can be worked into the model to be reproduced in metal.