NNP

Wire Edge.  A sharp protruding edge on a piece struck in a coining press where excess material squeezes out between the dies and the collar; a fin or burr. It is caused by excessive pressure or by oversized planchets. A wire edge is a form of flash and is evidence of sloppy presswork, however it is difficult to get a piece to fully strike up without a wire edge at the rim/edge juncture; this is sometimes done in case of expediency and the wire edge is trimmed off. Where no wire edge is present the struck piece is said to have a flat rim. In Great Britain a wire edge is called knife edge or knife rim.  See fin.

Reference:                                                                                                                             

NE42 {1992} Doty, p 344.

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