2000-P Jefferson Nickel
Struck on 1978 Denver Cent
ANACS MS 63 RB 1 of 2 Known
This major mint error is a recent discovery coin and 1 of 2 known. It is a double denomination (a nickel struck on a struck cent) with a dual date (different dates 22 years apart) and with dual mint marks (struck at both the Denver and Philadelphia Mints).
It is one of the most intriguing and rare mint errors that I've ever handled.