How did the piece-mold process differ from the lost-wax method?

The piece-mold process and the lost-wax method differ primarily in how the mold is constructed and how the molten metal is introduced to the form.

Piece-Mold Process

Used extensively for ancient Chinese bronzes, this method involves creating a clay model of the desired object, which is then encased in clay molding. This outer molding is cut into several sections, removed, and then reassembled around a central clay core to create the casting cavity. Because the mold is made of rigid sections, patterns were often incised directly into the mold pieces before they were reassembled and filled with molten bronze. Once the metal cooled, the mold was broken away to reveal the object.1

Lost-Wax Method

In contrast, the lost-wax process utilizes a wax model as the intermediary. A wax shell is created over a core and then covered in a heat-resistant investment material. The entire assembly is heated, causing the wax to melt and drain away, leaving a hollow cavity between the core and the outer investment. Molten metal is then poured into this empty space. Unlike the piece-mold method, which relies on reassembling rigid clay sections, the lost-wax method allows for highly complex, refined forms by eliminating the wax positive during the heating stage.23