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 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 ...

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 ...

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.

The Royal Mint has revealed some of the rarest coins to enter circulation during the reign of Queen Elizabeth II. Rare coins ...

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 ...

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 ...