The term is actually mint mark rather than mint "stamp".
There are four US mintmarks that are currently in use and a four additional historical ones. They are an "S" for the San Fransisco Mint, "D" for the Denver Mint, "W" for the West Point mint, "P" (and on pennies and older coins, no mintmark) for the Philadelphia Mint. And historically there was a "CC" for the Carson City Mint, an "O" for the New Orleans Mint and on some older gold coinage (1838-1861) a "D" refers to Dahlonega Mint, keep in mind that the Denver Mint is much newer and the mintmarks were never used simultaneously.
In 1964, the US mint was making coins primarily at two sites, Philadelphia and Denver. To distinguish the coins, the Denver coins had a D under the date. The Philadelphia coins had no mint mark.
They were coins minted by the Philidelphia mint
If your coin does not have a mint mark then it means it was minted at the Philadelphia mint. These coins are usually not as rare. However recently P mint marks were added to coins to indicate that they were made at the Philadelphia mint.
Only a very high grade Mint State coin would be woth more than 25 cents. NOTE: Coins have Mintmarks not stamps.
The mint mark "S" on US coins means the coin was minted in San Francisco, California. For more information concerning mint marks visit the site at the related link, below. Coins produced at the Denver mint have a "D" and those at the Philadelphia mint have either no mint mark (for pennies and coins before 1980) or a "P" for all other denominations. Coins produced at the mint at West Point, NY (largely bullion coins, although some 1996 dimes were produced there) have a "W" mint mark.
The letters are called Mintmark's NOT mint stamps. They are used to identify which mint the coin was made at.
Yes, Maria Montessori has been featured on various stamps and coins from different countries, including Italy and India, to honor her contributions to education and child development.
The U.S. Mint does not assign grades to any coins it sells. But Proof and Uncirculated coins do have different grades.
I have 4 volumes of coins of all nations, with stamps that we purchased some 15-20 years ago. What is their worth.
The set should have coins from the Denver mint & the Philadelphia mint. 5 from each mint
The mint mark is located in different places depending upon the coin and the date it was minted.
Nobody knows for sure! It is always a guess. Most collectors do not do it for the investment value, but for the enjoyment of the hobby.
All coins come from a mint. Casino coins are sometimes solid silver.
Coins
The US Mint produces circulating coins, commemorative coins, and bullion coins for the United States.
Coins are made in a facility called a mint.
Platinum Bullion coins are produced at the Philadelphia Mint and West Point Mint.