Educational Series: What is an RPM ?
How to tell if a coin is a Re-punched Mint mark (RPM)
Prior to 1990, the US mint used to take the working dies that made coins and added a mintmark to those working dies. If the coins were minted in Denver, they would add a “D”. If the coin was struck in SanFrancisco the US Mint would add a “S” to the working dies.
The Re-punched mint mark (RPM) has been deemed as a “variety”, since the US mint employee added an in