Prototype
Prototype. A struck piece with some unacceptable design element that requires change of design and a new die. As a forerunner to a more acceptable production run piece a prototype is the first of new type that proves to need a correction before final acceptance. A prototype requires a change of dies; the term is close to transitional design which requires a change of design. Numismatic writer Walter Breen used this term for a number of coin designs including the 1856 Flying Eagle cent, the 1882 Liberty Head nickel, the 1877 $20 gold piece and others. The author has not observed its use for medals.
References: NC8 {1988} Breen.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