Three sisters inherited their brother’s coin.

If you have a collection of coins at home, you may want to check their value. Three sisters from Ohio just sold a rare dime for $506,250 during an online auction.

The sisters’ mother and brother (who wish to remain anonymous) purchased the coin in 1978 for $18,200. The coin remained in a bank vault for more than 40 years until it was inherited by the sisters following the death of their brother. The sisters shared with news week that his family owned a dairy farm and kept the valuable currency for their financial security. One of the sisters had never even seen the coin until last year.

The 1975 coin features a portrait of President Franklin D. Roosevelt and is part of a collection of proof dimes. The coin has an error that adds value: a missing S mintmark, which indicates where the coin was produced. It is one of two in the collection that contain this error.

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“Mint marks hold the manufacturer responsible for the quality of a coin,” according to the United States Mint. “When the United States used precious metals such as gold and silver to manufacture circulating coins, a commission evaluated the metallic compositions and quality of the coins from each of the Mint facilities. “The evaluations ensured that each facility produced coins to the correct specifications.”

According to the lot listthe San Francisco Mint produced a “proof” set of more than 2.8 million coins. Three years later, collectors discovered that two of the dimes were missing the “S” mark. “This is a very exciting coin for our company to auction,” said Ian Russell, president of GreatCollections. news week. “We have handled many trophy coins over the years, including two 1913 nickels and two 1804 silver dollars, but this is the first time this is a 1975 non-S proof dime.” .

The dime was displayed at a coin show in Tampa, Florida, before being sold at an online auction on October 27, where it sold for more than half a million dollars.