A fold-over coin is one of the most dramatic types of errors. It occurs when the blank is standing vertically between the dies. During the strike, the force is so great that it bends and folds the blank. These fold-overs can be on-center or off-center, and come in many different shapes. There are a few fold-overs with multiple errors, either with an additional strike or fold-over. Denominations above quarters are very scarce.
This is the only known fold-over for a Connecticut State Quarter and only the second known for the entire State Quarter Series. Foldovers are extremely rare in higher denominations.