You will need to show it to an expert to know for certain.
An "S" mintmark just means that the coin was made in the San Fransisco Mint.
The 1884-S Morgan is a common date/mint coin in the circulated grades. But in the Mint State grades, it becomes a "Conditional Rarity" and do have much higher values.A certified MS-63 example of this coin currently has a market value of $38,000.00 to $40,000.00.
Please look at the coin again. The only way this year can be given a MS grade is if it has a "S" or "CC" mint mark. The Philadelphia issue coin is a Proof only coin and is valued at well over $50,000.00
It depends on the type of coin the date and denomination on were the mint mark is located
If your coin has a "S" mint mark on it means that it was made at the San Francisco mint in California.
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.
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 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.
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 means it was made at the San Francisco mint.
It means that the coin was minted at the San Fransisco mint. If a penny has a D, it means the coin was minted at the Denver mint. If it has no mintmark, it was minted at the Philadelphia mint.
The "S" and the "D" are called mint marks which identify which US Mint produced the coin. Coins with no mint mark prior to 1980 were minted at Philadelphia. Just having an "S" or a "D" mint mark does not mean the coin is worth more. The value of a coin is generally determined by the demand collectors and investors have for the coin. The more people who want to own it, the more it is worth.