The running joke is that "Good, isn't". G (or G4) means that a coin has a recognizable date and mint mark (if any) and all major details are visible, but the coin is otherwise quite worn down.
Except for extremely rare coins, "Good" is considered the lowest collectible grade.
The running joke is that "very good, isn't". VG means that a coin is quite worn, but with some of the more minor details still visible.
It's one step above Good, the lowest collectible grade. A coin in Good condition has a recognizable date and mint mark (if any) and all major details are visible, but the coin is otherwise quite worn down.
A coin that shows little traces of wear.
In coin collecting, it means Brilliant Uncirculated, a very nice coin, but not as good as a Proof coin.
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
A coin described as "Premium Quality" is an above average example.
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 collection is called, well, a coin collection. The hobby of collecting coins is called numismatics.
a coin collector
It means "premium quality". It is not an official form of grading.
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.
A coin which has "circulated" shows evidence of use in commerce, such as luster interruption, wear, circulation marks, dirt, etc. Conversely, an "uncirculated" coin displays no such evidence.
Numismatology