Caligula and Divus Augustus, AR denarius, (3.50g) c. 37-38 AD,
Lyons Mint, 

C CAESAR AVG GERM P M TR POT Bare head of Caligula right. 
No legend, Radiate head of Divus Augustus right between two stars. 

RIC 2; RSC 11; BMC 4.

With permission of numislanz.de, Auktion 102, lot 470