Rare Dime Bought by Ohio Farm Family and Hidden for Decades Fetches $500,000 at Auction

A 1975 proof set dime mistakenly made without the San Francisco Mint's letter S mintmark is shown in this undated image. GreatCollections via AP

TOLEDO, Ohio—An extraordinarily rare dime whose whereabouts had remained a mystery since the late 1970s has sold for just over $500,000.

The coin, which was struck by the U.S. Mint in San Francisco in 1975, depicts President Franklin D. Roosevelt and is one of just two known to exist without its distinctive “S” mint mark.