On U.S. coins dated 1968 and later, the letter indicates the mint where the coins were struck. It's called a mint mark.
No mint mark = Philadelphia (all cents, dollars 1971-78, others 1968-79)
P = Philadelphia (1980-present)
D = Denver
S = San Francisco
Coins dated 1965-67 did not carry mint marks.
Before that, mint marks were usually - but not always - on the back side of U.S. coins. Knowing what letters to look for and where can be quite challenging. See the Related Link for specific information.
If you mean a "D" under the date, it's not an error, it's the Denver mintmark were the coin was made.
It's the year that the coin was minted. If you look under the date you can tell where it was minted, too: "D" = Denver Mint "S" = San Francisco No letter = Philadelphia
The "D" indicates the coin was minted in the Denver mint
It is the date it was minted (made).
It means that the coin is rare. For example a 1909-S VDB cent is a key date. This coin is rare.
If you mean a "D" under the date, it's not an error, it's the Denver mintmark were the coin was made.
It's the year that the coin was minted. If you look under the date you can tell where it was minted, too: "D" = Denver Mint "S" = San Francisco No letter = Philadelphia
The "D" indicates the coin was minted in the Denver mint
It is the date it was minted (made).
If you mean a "Mintmark" it's a letter not a number and the 1922 Peace dollar is the highest mintage most common date of all Peace dollars, retail values are $16.00-$22.00 depending on the grade of the coin.
It means that the coin is rare. For example a 1909-S VDB cent is a key date. This coin is rare.
I suppose you're meaning the letter under the date on a coin??? "D" is for Denver, "P" is for Philadelphia. That indicates the mint that stamped the coin. It is also possible to have an "S" for San Francisco, or a "W" for West Point. On older coins you could also have an "O" for New Orleans, a "CC" for Carson City, a "C" for Charlotte, or a "D" for Dahlonega (on early gold coins).
Cents struck at the Philadelphia mint don't have a mint mark.
You need to give the denomination and date of the coin. Also where you see the 77 at on the coin.
A letter D just below the date is the mint mark for Denver.It is called a mintmark, and it signifies where the coin was minted.
If you mean no mintmark, it was struck in Philadelphia.
If you mean one of the Sacagawea dollars or a Presidential dollar the date is on the edge of the coin and its not gold.