The most valuable of those coins — a 1976 ... 1976-S Clad Proof Bicentennial Quarter: sold for $6,038 in 2010. 1976-S Silver Proof Deep Cameo Bicentennial Quarter: sold for $2,760 in 2007.
They were notable for being the first U.S. quarters in more than 50 years to feature a special reverse design. The most valuable of those coins — a 1976-S Bicentennial Silver Quarter that came ...