"Singular" 2018 Innovation Dollar Proof Set. Launched late in 2018, the American Innovation series' introductory small dollar was the only coin in the series produced that year, leading to this singular proof set. As the pioneer of the series, this coin fittingly features the signature of George Washington from the very first U.S. patent issued in 1790. Finest quality proof minting. 2019 Innovation Dollar Proof Set. Celebrating the pioneering efforts of innovators and inventions that helped shape the United States, the first full year of the small dollar series honors Delaware, Pennsylvania, New Jersey and Georgia. Each gold-colored proof boasts mirror-like backgrounds and frosted deep sculpted engravings.