A lowly five-cent coin with a remarkable history could fetch as much as \$5m (£3.18m) at auction in the US.
The 1913 Liberty Head nickel is one of only five known to exist.
It was cast illegally, discovered in a car wreck that killed its owner, declared a fake, forgotten for decades and then found to be the real thing.
"Basically a coin with a story and a rarity will trump everything else," said Douglas Mudd, curator of the Colorado museum which is holding the coin.
Conservative estimates put its value at around \$2m (£1.27m).
But Mr Mudd thinks the sale price could reach as much as \$5m (£3.18m).
"A lot of this is ego," he said of collectors who will bid for it when it comes up for auction on April 25 in Chicago.
"I have one of these and nobody else does."
The current US record is \$8m (£5.08m) for a 1933 Double Eagle, a \$20 gold coin.
The nickel was one of five struck surreptitiously by Samuel Brown at the Philadelphia mint in late 1912, the final year of its issue, but with the year 1913 cast on its face.
Mr Brown offered them for sale in 1920, and the set was broken up in 1942.
A North Carolina collector, George Walton, bought one for \$3,750 (£2,386).
The coin was with him when he was killed in a car crash in 1962, and was found among hundreds of others scattered at the crash site.
His sister was told it was a fake and stuck it in an envelope in a cupboard.
It remained there almost forgotten for 30 years until her death in 1992, when experts confirmed it was the long-missing fifth coin.
Four siblings who inherited the nickel will split the money equally after it is sold.