There's a marketplace for coin enthusiasts to buy and sell rare coins, where you could make some decent money if you find one ...

This rare coin is notable because it doesn’t contain a mint mark; the U.S. Mint deliberately didn’t include mint marks on coins produced from 1965 to 1967, to limit coin hoarding.

This rare coin is missing its "D" mint mark, and other varieties have noticeable but weak mint marks. The “no D” variety is by far the most valuable and has no trace of the mint mark whatsoever.

THREE sisters finally sold a rare coin with a missing mint for a whopping $500,000 ... It's extraordinarily rare because it makes up just one of two known coins to exist without an S mint mark ...

Rare penny coin with 'very valuable' mark worth fortune ... Content cannot be displayed without consent. ... The 1882 with a H mint mark is very valuable and has been known to sell for £280." ...

Some of the rarest and most valuable coins in U.S. history owe their worth to minting errors that slipped through unnoticed. Coins like the 1943 Copper Penny, struck in copper instead of wartime ...

Some mint marks are scarcer than others, like the S in this coin’s case, meaning that 1943-S steel pennies are often the most valuable (not including coins with rare errors). Mint Errors ...

1922 No D: The Denver Mint was the only one to produce pennies this year, but some were mistakenly minted without the “D” mint mark. Collectors highly seek after these.

You don't need to be a coin collector to have piggy banks stashed around your house filled with quarters, dimes, nickels or pennies. However, you may not be aware of the potential fortune you have ...

If your 1983 penny has no mint mark and a doubled effect, it could be worth thousands of dollars. How much is it worth? The U.S. minted about 7.7 billion pennies in 1983 but only about 5,000 of ...