A dime that sat for 46 years in an Ohio bank vault sold for over $500,000 last weekend, according to the California-based auctioneer that oversaw the sale.

The Proof 1975 Dime was minted in San Francisco in 1975 and bears the profile of Franklin D. Roosevelt. That year, the United States Mint produced 2.84 million proof sets, according to Ian Russell of GreatCollections, the California auctioneer who handled the sale.

What sets the dime apart from others of its time is that it lacks the “S” mark needed to be on all proof coins struck at the U.S. Mint in San Francisco, Russell confirmed to USA TODAY Friday morning.

It’s one of two coins made erroneously without the marking, Russell said in a news release about the sale. 

The dime that sold last weekend garnered over 200 bids Sunday night and sold for $506,250, nearly 30 times what the previous wonders paid for the coin 46 years ago in 1978. The sale set a new record, Russell said.

According to Russell, it was a Los Angeles customer who discovered the coin lacked the marking in 1977. The customer ordered five sets by mail and noticed that two of the five sets were missing the "S" marking.

The customer sold the first coin to a dealer, waited a few months and then sold the second coin, Russell said.

“At the time, there was already news of the 1968 and 1970 Proof Dimes lacking the ‘S’ mint mark in error, as well as the 1971 No S Proof Jefferson Nickel, so each year, it was fairly normal at the time to check proof sets to see if any coins had errors,” Russell wrote in an email to USA TODAY.

Same family owned rare coin for decades

While collectors have known about the two coins for some time, no one knew where they were since the late 1970s, Russell told USA TODAY.

Chicago dealer F.J. Vollmer sold the two coins in 1978 and 1979, Russell said.

The second coin resurfaced in a 2011 auction and sold for $349,600, then again in 2019, selling for $456,000. That coin is now with a collector who specializes in Roosevelt Dimes, Russell said.

According to Russell, an Ohio collector and his mother bought the recently sold coin in 1978 from Vollmer for $18,200. The owner kept the dime in an Ohio bank vault for more than 40 years. Once he died, his three sisters inherited the coin.

“The owner … always considered the coin a family asset,” Russell told USA TODAY. “It was bittersweet for (his sisters) – they knew how important it was to their brother – but also recognized he was getting closer to selling it - and that another coin collector should have the opportunity to own the coin.”

Russell said valuable coins are sometimes kept in vaults, sold once collectors have all the coins they need, and some coins are saved for future generations.

"The collector who bought the coin in 1978 and stored it for 46 years in a bank really had confidence in the rarity and long-term desirability of the coin," Russell said. "He took a risk that more would be discovered, but he told me he had a feeling that it was going to continue to be a major rarity. He bought it three years after it was minted, so it gave him some confidence there would not be others."

Saleen Martin is a reporter on USA TODAY's NOW team. She is from Norfolk, Virginia – the 757. Follow her on Twitter at@SaleenMartin or email her at[email protected].