Most pennies are worth 1 cent, but to coin collectors, some are worth more than their weight in gold.
Earlier this year, an ordinary looking penny made headlines when it was found among the possessions of a man named Don Lutes. The 1943 bronze Lincoln cent attracted nearly 30 bids and sold for $204,000 in January, according to Heritage Auctions, the organization that conducted the sale.
"The then 16-year-old Lutes received the copper-colored penny in change at his high school cafeteria in 1947," David Stone, a coin cataloger for Heritage, told CNBC Make It.
Lutes owned the coin until his death in 2018. In failing health, he consigned it to Heritage. Proceeds of the sale went to the Berkshire Athenaeum in his hometown of Pittsfield, Massachusetts, according to the Dallas-based auction house.
Hunting for precious pennies
"One-cent coins have been around since the beginning of the U.S. monetary system," Stone said. "Several prototypes for the cent were produced in 1792, including the large Birch cent."
The finest known 1792 Birch cent sold at a Heritage auction in 2015 for nearly $2.6 million, making it the most ever paid for a one-cent piece at auction, he said.
A penny's worth depends on its quality and rarity. While most pennies are only worth a few bucks, highly coveted ones might be sitting in your pocket or stuck somewhere in your couch cushions.
The odds are long, but they're still well worth searching for. So before you say, "Keep the change," check to see if you have any of these valuable pennies:
1. 1943 Bronze Lincoln
Only a handful of these bronze pennies have been discovered, including the one found by Lutes. "The most valuable Lincoln cent sold privately in 2010 for $1.7 million," said Stone.
In order to preserve copper for the war effort, the U.S. Mint switched to making pennies from zinc-coated steel planchets, instead of the usual bronze coin blanks, Stone explained. At least, that's what was supposed to happen.
As fate would have it, "some of the old bronze planchets got stuck in the big tote bins that the Mint used to feed the coin presses at the end of 1942," he said. "The few bronze coins that were struck went unnoticed and got released into circulation."
Today, the 1943 bronze Lincoln cent is described as "the most famous error coin in American numismatics" — and the odds of finding one are astronomically against.
Stone estimates that 15 to 20 are known to collectors today, although it's possible that there are a few that have not yet been accounted for.
"A nice circulated example, like Lutes' coin, could sell for around $150,000 to $200,000. Heritage auctioned a similar one — in slightly lower grade — for $186,000 earlier this month," he said.
Due to its value, some counterfeits were created with steel cores. If you think you've found a 1943 Bronze Lincoln, the Mint suggests testing it with a magnet first. If it sticks, it's not copper.
2. 1969-S Doubled Die Obverse
Doubled dies are created when the hub imprints an additional image onto a die — or stamp — causing some misalignment. The doubling occurs from mistakes in the minting process, James Bucki, a coin expert at The Spruce Crafts, explained to CNBC Make It.
The doubling on the 1969-S Doubled Die Obverse is especially prominent in the words "LIBERTY" and "IN GOD WE TRUST," he said. (Collectors refer to the obverse of a coin as the front or "heads" side — usually bearing a portrait.) Also, look for the letter "S" right below the year 1969, which means it was created at the San Francisco Mint.
Bucki estimates that 1,000 or less were made before the Mint discovered its error. A coin in good condition could go for about $75,000. Last year, one sold for $35,000, according to Coin World, a popular news and analysis website for collectors.
3. 1992 Close AM Reverse
"On the reverse of the 1992 Close AM, the right foot of the 'A' and left foot of the 'M' in 'AMERICA' touch," said Stone. (Most pennies minted that year have very definite spaces between those letters.)
This came about because in the 1990s and early 2000s, the Mint used different dies for producing coins for circulation and proof coins for collectors, explained Bucki.
But due to a mix-up, a proof die was used for the reverse of the coin before it was supposed to be used starting in 1993. It's likely that an entire run of 250,000 pennies were printed this way, he said. That makes them much easier to find than the 1969 Doubled Die coins.
Bucki estimates that a 1992 Close AM coin in fairly new condition could be worth about $20,000, while a used one could sell for around $2,000 to $3,000. One sold at a Heritage sale in 2012 for more than $20,000, according to Coin World.
4. 1972 Doubled Die Obverse
Similar to the 1969 Doubled Die, the doubling on this penny is especially prominent in the words "LIBERTY" and "IN GOD WE TRUST" — with some light doubling on the date, said Stone.
Bucki estimates that at least 250,000 coins released with the doubled die. "I know a couple of people who have found these in their pocket change."
A used one of these might be worth about $100, while a cleaner one could go for $500, he said.
