What this coin looks like (obverse, reverse, mint mark location, special features, etc.): There were two major varieties of the 1839 Seated Liberty Half Dollar. This newer variety features the addition of drapery added under the elbow on the right side of the liberty portrait as depicted above. The older version did not incorporate this small bit of drapery into the liberty portrait.
Coin value chart: Typical coin prices, values and worth in USD based on grade/condition