Diocletian AE follis. 

Obv: IMP CC VAL DIOCLETIANVS PF AVG, radiate, draped bust right 
Rev: CONCORDIA MILITVM, Emperor standing facing right, holding parazonium, 
 receiving Victory from Jupiter standing facing left, holding sceptre. 
Gamma in lower centre.
Mintmark: dot XXI dot.

RIC V-2 Heraclea 284, unlisted officina mark

Contributed by Dane for George Clegg (biggyg2), December, 2005.