President Roosevelt died on April 12, 1945, and Treasury officials soon proposed putting his portrait on a circulating coin. The dime was the natural choice. Roosevelt was believed to have had polio (CoinWeek notes that recent research points to Guillain-Barré syndrome instead), and the March of Dimes, the fund drive he championed to fight the disease, had already tied his name to the ten-cent coin. An 1890 law also let the Treasury change a design after 25 years without asking Congress, and the Mercury dime had been in use since 1916.
The work went to John R. Sinnock, the Mint's Chief Engraver since 1925. The Commission of Fine Arts turned down his first models and asked for an open competition, but Mint Director Nellie Tayloe Ross refused, because the coin had to be ready for January 30, 1946. That was Roosevelt's birthday and the start of that year's March of Dimes campaign, and the new dime was released that day.
Controversy followed. As Cold War fears grew, a story spread that the JS under Roosevelt's neck stood for Joseph Stalin. It was false; the letters are Sinnock's initials. Others said Sinnock had borrowed his profile from a plaque by the sculptor Selma Burke. CoinWeek, comparing the two, finds them similar but not the same. Sinnock died in May 1947.
Philadelphia, Denver and San Francisco all struck dimes until early 1955, when San Francisco stopped coining after the first three months of the year. From 1956 to 1964 only Philadelphia and Denver made them. Proof dimes, offered only in complete sets from 1950, were struck every year from 1950 to 1964.
Collectors saved new rolls every year, and they hoarded the issues whose mintages were reported as low, such as the 1949-S and the three 1955 dimes. The coin shortage of the 1960s then pushed production to its peak. Congress froze the date at 1964, so about three quarters of Philadelphia's 1964 dimes were made in 1965, and Denver kept striking 1964-dated dimes into 1966. The Coinage Act of 1965 replaced silver with copper-nickel clad.
