Diocletian AE Follis, 296-297 AD, Trier. 

IMP DIOCLETIANVS AVG, laureate, draped, cuirassed bust right, seen 
from the back
GENIO POPV-LI ROMANI, Genius, standing left, modius on head, naked,
 except for chlamys over left shoulder, holding patera and
 cornucopiae. 
A in left field, Gamma in right field, mintmark TR in ex. 

RIC VI Trier 190a. Rare.

With permission of Roma Numismatics, October, 2009