Second Strike Misalignment (Horizontal)
A horizontal, vertical, pivoted, or rotational misalignment can occur on the second strike after a normal first strike. It’s also possible for a misaligned die strike to precede a normal second strike, although this has only indirectly been documented through clash marks.
In this 1999 cent, the hammer (obverse) die was centered during the first strike. Between the first and second strike, it shifted to the right about 10%. Before the hammer die descended a second time, an unstruck planchet intruded into the striking chamber, leaving an indent on the left side. Details of the first strike can be seen in the floor of the indent. The second strike also show a partial collar error.