Part IV. Die Errors:

Die Deterioration/Deformation Errors:

Peripheral Die Expansion and Erosion

Definition: This error is characterized by radial expansion of the die face, excluding the rim gutter.  The field portion of the die face and the peripheral design elements migrate outward, forming a thin shelf over the rim gutter that is immediately and continuously eroded.  The result is abrupt truncation of the peripheral letters where they crowd against the design rim.  This error has so far only been detected on some 1982 cents, but it probably more widespread.

Both faces of this 1982 cent show peripheral die expansion and erosion.  Observe how the outer portions of the peripheral letters are abruptly truncated where they abut the design rim.