Diocletian. 284-305 AD. Antoninianus (3.56 gm). Cyzicus mint. 
IMP C C VAL DIOCLETIANVS AVG, radiate and draped bust right.
CONCORDIA MILITVM dot, Emperor standing right, holding parazonium or sceptre, receiving Victory from Jupiter
standing left, holding sceptre.

A in lower centre.
Mintmark XXI dot.

RIC V-2, 306; Cohen 33