A coin collection is called, well, a coin collection.
The hobby of collecting coins is called numismatics.
Numismatology
The study or collection of currency is called Numismatics. This includes paper money, tokens or coins. This term can also include the study of money in general.
It means the front side the "heads" of the coin. The reverse is the opposite end often called the "tails" of a coin.
a coin collector
Coin collecting
While the president has not said much about coin collecting, he has said a lot about education and about the importance of hobbies that are educational. Both stamp collecting and coin collecting teach about geography and about important historical figures, so the chances are, he would be in favor of such hobbies.
Coin collecting
It is called a "mini coin". They are manufactured as a novelty and have no numismatic {fancy word for coin collecting} value.
RPM is a coin collecting slang for "Repunched Mintmark". It refers to when the mintmark on a coin has been struck twice, and you can see remnants of the first mintmark underneath the second mintmark.
Lots of wear on the coin and the lowest grading possible.
edge of a coin with grooved lines that run around the entire perimeter of the coin
In coin collecting, it means Brilliant Uncirculated, a very nice coin, but not as good as a Proof coin.