What this coin looks like (obverse, reverse, mint mark location, special features, etc.): The 1979 S Proof Jefferson Nickel was produced in two types. One type was the Type 1 Filled S in which the mint mark was not as clear and partially filled in - depicted on the left side of the mint mark comparison image. The second type was the Type 2 Clear S in which the mintmark was clearer and larger - depicted on the right side of the mint mark comparison image.
Coin value chart: Typical coin prices, values and worth in USD based on grade/condition