Définition

• Silvered.  A metal finish, actually a coating, of gray color with a metallic luster. It is applied by dipping the object to be silvered in a silver cyanide solution similar to silvering the back of mirrors. It is not accomplished with electrical current (it would be silverplating if it were) but is a chemical bonding or coating to metal. Usually applied to copper, bronze or brass objects that are already fabricated – and coins after they are struck – such silvered coating is in imitation of solid silver or silverplating. When first applied it is highly reflective; but this is not a stable lustrous finish, however.
  The silver coating is extremely thin (in this regard it is similar to flash plating because of this thinness). When silvered items bleed (wear thin) they quickly expose the color of the base composition, the same whether the item was silvered or silverplated.  See bleeding.
  In time all silvered coins (and objects that are much handled) will turn dark to muddy gray and be worn off in selective areas (high points and other wear points). Because of this it is not difficult to differentiate a silvered specimen from one that is silverplated – the muddy gray color identifies the silvered item while a lustrous silver color indicates a solid silver or silverplated specimen. Thus silvered items are to be found in the numismatic field only applied to ancient coins (when the process was first employed) and to very cheaply made medals and tokens produced later.
  References:                                                                                                                         
  B20 {1972} Hall and Metcalf, "Surface-silvered Ancient Coins" by Lawrence H. Cope.

  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

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