Original door knocker designs are modeled in wax, and made into a metal pattern. Pattern is used to make sand castings in yellow or red bronze. Raw castings are worked on using grinding and polishing wheels. Door knockers are assembled mechanically or welded, and patinated with chemicals or plated with nickel. One-of-a-kind door knockers have inset stones which are cut, shaped, and polished using lapidary equipment and techniques.