Mint-made errors 5 centavos. Foreign coins struck on a U.S coin planchet or vice versa are very uncommon and hold a high value. Authentic error coins should not be confused with coins that are damaged after being minted, which is known as post-mint damage (PMD) or post-strike damage (PSD). Mints purchase long strips of metal which are fed through blanking machines that punch out disks known as blank planchets (or simply as planchets or blanks) on which coins are struck. This determines the size and shape of eventual coins. The punched disks are first known as "type-1 blanks (or planchets)". The disks
Sheet metal Sheet metal Sheet metal is metal formed by an industrial process into thin, flat pieces. Sheet metal is one of the fundamental forms used in metalworking and it can be cut and bent into a variety of shapes. Countless everyday objects are fabricated from sheet metal. Thicknesses can vary significantly; extremely thin sheets are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate steel or "structural steel." Sheet metal is available in flat pieces or coiled strips. The coils are formed by running a continuous sheet of metal through a roll slitter. In most