NGC 1977-S proof Jefferson nickel struck on a clad dime planchet. The coin is smaller than a normal nickel, with much of the outer lettering missing, and also the coin weighs 2.3 grams (normal for a nickel is 5.0 grams.)
A very scarce error type for proof nickels, with and estimated 12-15 examples known for the Jefferson nickel series struck on dime planchets.
PF68 Ultra Cameo with heavy frost on the obverse and reverse. A beautiful example!