I don't believe there any known after 1956. They would be nearly impossible after 1990 when the mintmarks were added to the Master dies and then the mdels the master hubs were created from. Only way to happen would be a major doubled die with a die being hubbed by both a business strike hub and a proof hub. And completely impossible after 1996 because the mintmarked dies weren't even made in the same facility.
Disclaimer: While a tremendous amount of effort goes into ensuring the accuracy of the information contained in this site, Coin Community assumes no liability for errors. Copyright 2005 - 2026 Coin Community Family- all rights reserved worldwide. Use of any images or content on this website without prior written permission of Coin Community or the original lender is strictly prohibited. Contact Us | Advertise Here | Privacy Policy / Terms of Use