What this coin looks like (obverse, reverse, mint mark location, special features, etc.): This is the later version of the 1836 Capped Bust Half Dollar. The standard lettering on the edge of the coin (FIFTY CENTS OR HALF A DOLLAR) was removed and replaced with a reeded edge (vertical lines). In addition: The "50 C." denomination at the bottom of the reverse of the coin was changed to the words "50 CENTS". This variety is very rare and valuable - also very easy to identify.
Depicted below is an example image of what the reeded edge looks like:
Coin value chart: Typical coin prices, values and worth in USD based on grade/condition