Watch List notes:

Gaius, called Caligula (37-41), Quadrans, Rome, AD 39-40; AE (g 3,38; mm 19; h 6); C CAESAR DIVI AVG PRON AVG, round pileus between S - C, Rv. PON M TR P III P P COS TERT, round R C C. RIC 45; C 6.
Green patina, good very fine.