Materials & Techniques

Lost-Wax Casting

The lost-wax casting method creates a single unique image, as opposed to one that is cast from a mold of an existing image. Sculptors mold images out of wax comprised of a mixture of beeswax and tree resin. Once the wax is fully molded into the key pieces of the final sculpture, it is placed in cold water to harden. The pieces of wax are joined after being reheated and connected with tubular struts. While the wax is malleable and sticky, sculptors form every detail because every mark on the mold will register on the finished metal cast sculpture.

The wax image is then covered with an outer mold of layered clay, and the entire piece is held together with metal wire suitable to the heat of fire. The clay-encased mold is baked, and the wax is then melted from the outer mold and molten metal is poured into it. After cooling for several days, the clay mold is broken open to reveal the metal sculpture within. The bronze is polished and smoothed and any excess clay or bronze chipped away to create the finished product.

Adapted from

  • DMA unpublished material.

Web Resources

  • Smarthistory
    Watch a video about lost-wax casting.
  • Khan Academy
    Watch a short video that demonstrates the creation of an ancient Roman silver cup, including repoussé, chasing, and lost-wax casting.