'Holy grail' found: Rare penny might be worth $1.7M after it was found in boy's lunch money

Now that's a pretty penny.

A penny that a Massachusetts teenager found in his change from lunch money could be worth as much as $1.65 million (£1.3 million) when it is auctioned off.

The 1943 Lincoln penny is made up of copper and has been described as the "most famous" coin made in error, according to Heritage Auctions, which is auctioning off the coin. Only 20 were ever made and for years the U.S. government denied its existence, but one coin was found by Don Lutes Jr. in his school cafeteria in March 1947.

"Despite relentless searching by eager collectors over a period of more than 70 years, only a handful of legitimate specimens have ever been discovered," Heritage wrote on its website. "PCGS CoinFacts estimates the surviving population at no more than 10-15 examples in all grades. We have compiled a roster of all specimens certified by the two leading grading services below, including an unknown number of resubmissions and crossovers."

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