PART VI. Striking Errors:

Machine Doubling:

Machine Doubling on Both Faces of the Same Coin

Definition: This form of doubling typically results from vibration or instability affecting the die, die assembly, or press frame.  It has also occasionally been blamed on a coin sticking to the anvil die during ejection (“ejection doubling”). At times, machine doubling can affect both the obverse and reverse face of the coin.

This 1991(P) Lincoln cent has been affected by machine doubling on both the obverse and reverse faces of the coin.

The 1991(P) Lincoln cent pictured above may have been struck by the same dies as the 1991(P) Lincoln cent shown first. Both the obverse and reverse of this coin show exaggerated shelf-like machine doubling.

This coin is courtesy of Cindy Helms.