1993 Lincoln Cent Double Face

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Split Plating Doubling

Definition: Best expressed and most often seen among broadstrikes and off-center strikes, split plating doubling is restricted to copper-plated zinc cents. When the planchet is struck, the portion trapped beneath the dies expands in all directions. The thin copper plating is subjected to tensile as well as compressive stress. The tensile stress causes the copper plating to rupture, exposing the underlying zinc. The exposed zinc often outlines large centrally-located design elements, like busts and buildings. Split plating doubling can, however, involve any design element, including peripheral ones.

Another factor involved in split plating doubling is a tendency for the copper plating to catch on the sharp corners of the recesses in the die face. This can tear open the copper plating as the coin expands.