Lost Wax Casting Process Most detailed are cast using the “Lost Wax” process. This is the most precise metal casting technique in existence, ensuring accurate reproductions of the original sculpture and exquisite detail. All bronze pieces are cast from a wax model regardless of the original material the model was sculpted in usually in clay or wax. “Lost wax” casting method was found in thousand years ago. Even though, modern methods and materials have improved the technique. It is still an extremely labor intensive and expensive process.