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. The earlier variety features no drapery under the elbow on the right side of the liberty portrait as depicted above. The newer version included the addition of this drapery under the elbow.
Coin value chart: Typical coin prices, values and worth in USD based on grade/condition