A Chief Engraver whose portraiture shaped the Roosevelt dime and whose Franklin half-dollar work was completed after his death.
Biography
Sinnock joined the Mint as an assistant engraver and succeeded George Morgan in 1925. He produced medals and commemoratives as well as circulation designs during the transition from the classic sculptor competitions to an internal engraving staff.
Style and legacy
His portraits use smooth, compressed modeling and clear inscriptions. The Roosevelt dime reverse combines a torch, olive branch, and oak branch in a compact symbolic field. The dime remains in circulation. On the Franklin half dollar, Sinnock's portrait and Liberty Bell concept were completed for production by Gilroy Roberts, so credit should not be flattened to one name.