The images to the left are examples of cents with
Lamination errors.  

Laminations are a result of a coin being struck on
a defective planchet.  Planchets can become
defective when dirt and impurities force the
planchet to crack & peel.  Laminations can be a
thin raised piece of metal on the surface of the
coin (such as the top image) or a missing area of
the planchet (bottom image).  

Laminations very in size and severity.