Jig
Jig. A metal form to enclose or hold a medallic item while some operation is performed on it. A jig made as a form mold and cut into portions can be used in partial plating, for example. See nest, mask, partial plating.
excerpted with permission from
An Encyclopedia of Coin and Medal Technology
For Artists, Makers, Collectors and Curators
COMPILED AND WRITTEN BY D. WAYNE JOHNSON
Roger W. Burdette, Editor