It depends on the type of coin the date and denomination on were the mint mark is located
The letter is known as the mint-mark and tells where the coin was made. A coin having a P mint-mark (or no mint-mark on some coins) was made in Philadelphia, a coin having an S Mint-mark was minted in San Fransisco, a coin with a D mint-mark was minted in Denver.
A mint mark tells where the coin was minted, for example, a P mint mark (or in some cases no mint mark) signifies the coin was minted in Philadelphia, D is for Denver, S is for San Fransisco. I'm assuming someone told you that the mint mark was under the eagle for whatever coin you had, so you simply need to look under the eagle to find a mint mark. Keep in mind that some coins were produced in the Philadelphia mint and have no mint mark.
On the reverse of the coin under the wreath. It's a S or O mint mark, but without a mint mark it was struck in Philadelphia.
The S is the mint mark of the San Francisco mint, where the coin was made. that is not a question it is an answer
If it has one it would be located on the reverse side of the coin just above the letter "D" in the word "DOLLAR". The mint mark "S" is for San Francisco, California. The mint mark "CC" is for Carson City, Nevada. If there is no mint mark the coin was struck at the mint in Philadelphia, Pennsylvania.
The letter is known as the mint-mark and tells where the coin was made. A coin having a P mint-mark (or no mint-mark on some coins) was made in Philadelphia, a coin having an S Mint-mark was minted in San Fransisco, a coin with a D mint-mark was minted in Denver.
A mint mark tells where the coin was minted, for example, a P mint mark (or in some cases no mint mark) signifies the coin was minted in Philadelphia, D is for Denver, S is for San Fransisco. I'm assuming someone told you that the mint mark was under the eagle for whatever coin you had, so you simply need to look under the eagle to find a mint mark. Keep in mind that some coins were produced in the Philadelphia mint and have no mint mark.
If you know it's a 1921 "S" Morgan you found the mint mark
The mint mark of the Denver Mint (shown as a "D") and the San Francisco Mint (shown as "S) on the Eisenhower Dollar is located on the obverse (heads) side of the coin directly beneath the bust of Eisenhower. If there is no mint mark there, then the coin was struck at the Philadelphia Mint and in this mint did not place a mint mark on the coins struck there until 1979.
If your coin has a "S" mint mark on it means that it was made at the San Francisco mint in California.
On the reverse of the coin under the wreath. It's a S or O mint mark, but without a mint mark it was struck in Philadelphia.
The S is the mint mark of the San Francisco mint, where the coin was made. that is not a question it is an answer
It's a mint mark indicating where the coin was made: > No mint mark = Philadelphia > D = Denver > S = San Francisco
The S above the date is the mint mark for the San Francisco mint and identifies it as a proof coin for the Eisenhower seires of dollar coins.
A mint-mark on a coin is a letter designating the location of the mint where the coin was made. "D" for Denver, "P" for Philadelphia, "S" for San Francisco.
Please post a new question with the coin's denomination. If you can find a small D or S mint mark on it include that detail as well.
Please post a new question with the coin's denomination.