Watch List notes:

Gaius, called Caligula (37-41), Denarius, Rome, AD 37-38; AR (g 3,71; mm 19; h 4); C CAESAR AVG GERM P M TR POT, laureate head r., Rv. DIVVS AVG - PATER PATRIAE, radiate head of Divus Augustus r. RIC 16; C 2.
Rare. Cabinet tone, about extremely fine.