What this coin looks like (obverse, reverse, mint mark location, special features, etc.):
There were two major varieties of the 1864 Indian Head Cent (Penny). One variety has an "L" on the ribbon behind the Indian head and the other one does not have an "L". The "L" stands for the initial of the last name of James Longacre who designed the coin. This would also be a new feature that would be minted on all future Indian Head Cents. The "L" or lack of "L" is depicted by the example image above.
Coin valuation chart: Typical coin prices, values and worth per grade or condition - in USD