Use this app to see mint error and variety images (doubled dies) coins so you can learn what they look like and how much they're worth. App has detailed descriptions of each mint error along with images to help you identify doubled dies, rpms, repunched mint marks, off center coins, mules coins, capped die, struck through coins, strike through, floating roof, doubled dye, misaligned die, mad, missing date, missing number, missing letter, dropped letter, over date, misplaced date, off metal planchet, wrong metal planchet and many more mint errors.
A great resource for mint error coin collectors and people who search for doubled dies and repunched mint marks as well as mint errors in their change, rolls or coin collections.