Correction: This story and headline have been updated to remove an incorrect estimate of the possible selling price. The auction house estimate was $170,000, not $1 million.

A rare coin a teen received from his school cafeteria could fetch six figures at auction.

The penny was produced accidentally in 1943, according to Heritage Auctions, where aspiring buyers are bidding on the coin. The penny was created after "a small number of bronze planchets was caught in the trap doors of the mobile tote bins used to feed blanks into the Mint's coin presses at the end of 1942," according to auction house.

Rare 1943 bronze penny Heritage Auctions, HA.com

Those bronze planchets then fed into the coin press, leading to the creation of several coins that were "lost in the flood of millions of 'steel' cents struck in 1943." That year, during World War II, the U.S. Mint was striking one-cent coins using zinc-coated steel instead of previously-used copper, which is used in bronze. During the war, copper was considered strategic, said Heritage Auctions.

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Today, the Dallas-based auction house describes the 1943 bronze Lincoln cent as "the most famous error coin in American numismatics."

High school student Don Lutes, Jr., of Massachusetts, came across one by chance — back in 1947.

When he found one in cafeteria change in March that year, he was "old enough to remember the 'steel' cents struck in 1943, which were still commonly seen in circulation at the time, so this copper-colored example aroused his curiosity," according to Heritage Auctions. "As a coin collector, he set the coin aside for future study, but did not publicize his find until years later."

The top bid for the coin as of Wednesday morning was $120,000. As Fortune reported, in 2010, a different 1943 penny created with a bronze planchet sold for $1.7 million.

"This lot represents a true 'once in a lifetime' opportunity," said Heritage Auctions, which estimated it could sell for $170,000 or more.

According to multiple reports, Lutes died in September.