Referring to the top picture, Your coin on the left is a Small date, while the coin on the right is a Large date.....That said, Mint marks can not only appear different like CWB mentioned, but actually be completely different. Just like different dies used for the coins themselves, different dies are also used for the mint marks. Up until a certain point in time as well, ALL Mint marks were pressed in one mint ( I think Philadelphia), and then shipped to the respective mint.




























