The art of the lost wax process: The earliest known lost wax castings date from nearly 7,000 years ago. Metals were poured into investments of fired clay that had been shaped with the help of wax that was melted or lost. Then sometime between 4,000 and 3,000 B.C. , bronze was discovered as being a metal that was harder than copper or tin alone. Ancient lost wax bronze castings have withstood centuries, visually telling the tales of past cultures. Many of these cultures have since grown obsolete, their religions have evolved and societies have changed. Elements of the lost wax process have been refined. Yet today, bronze casting is essentially the same as it was in 2,000 B.C. Bronze is 95% copper, 4% silicon and 1% manganese with traces of other elements such as iron. Silicon bronze has been the bronze choice for fine art castings since its development in the 1920s. It is corrosion resistant, strong, resilient, formable and weldable. Also known as hot cast bronze, a fine art lost wax casting of silicon bronze is created through many labor intensive steps. 1. Making the Original Clay Sculpture. To begin the process of making a bronze sculpture, most sculptors choose to make an original out of clay. The three main categories of clay used for sculpture are water based clay, oil based clay and self hardening low fire clay. Choosing the proper clay for a particular project may simply be a matter of preferance. Experience, however, is perhaps the best teacher when deciding what type of clay to use. Most artists prefer to work with oil based clay. The main reason for working with oil based clay is because it never dries or hardens. It can always be softened and reworked if a change needs to be made. The main concern with using oil based clay is how to have the clay soft enough to build the sculpture rapidly and yet at the same time have the clay hard enough to produce good detail. The usual solution is to choose a clay that is hard enough for detail work and then just use heat to soften the clay for buildup. Very small sculptures are often modeled directly in wax which, though more difficult to model, allows for maximum detail. End of Part 1