Acmonital. An alloy of stainless steel. Coins in stainless steel were first struck in Italy in 1939, in both a magnetic steel and nonmagnetic alloy (1939-43). The alloy is hard, die wear is high, and only low relief designs can be struck in coining presses (but Italy had experience in striking a hard nickel alloy since 1919). Its use in 1939 was a wartime alloy , but an acmonital alloy was resumed for Italian coins in 1954 and used continuously afterwards. In 1982 it was the composition of the outer rim on the first bimetal composition for an Italian 500-lire coin (see bimetal). Acmonital is an acronym for Acciaio Monetario Italiano.
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