Metalworking in Bronze Age China: The Lost-Wax Process By Peng Pe ...

Chapter 1

What Is Lost-wax Casting?

Principles of the Lost-wax Process

Casting (or founding) is the process of pouring molten metal into a refractory mold with a hollow cavity and allowing it to solidify into the desired shape.¹ The earliest-known castings in the global archaeological record were made in open stone molds.² Stone, as a durable material, allows for the repeated casting of a relatively simple shape from the same open mold. Metalworkers in time devised the closed mold, which was cut in stone or, more frequently, fashioned in clay.³ Of these closed molds, the bivalve or two-piece mold, consisting of two abutting halves, was decidedly the most rudimentary, capable of casting only simple tools and weapons, such as axes, adzes, daggers, knives, and spearheads.⁴

Stone molds, whether open or bivalve, were manufactured by carving or cutting directly in stone, likely with only a conceptual model in mind. The clay bivalve mold, in contrast, seems to have been taken in two pieces from a physical model and subsequently pressed together. The use of a tangible model undoubtedly provided better control of the shape and dimensions of the final casting. In fact, such a model was essential when the desired shape of the finished object became too complex to be