Constantine I, AE3, Cyzicus.

CONSTANTI-NVS MAX AVG, laureate, draped, cuirassed bust right.
GLOR-IA EXERC-ITVS, two soldiers holding spears and shields 
with two standards between them, dot in o on banners.

Mintmark: dot SMK delta.

RIC VII Cyzicus 95, rated R4.

From Dane's collection, July 2010.
(I know, it's a very worn reverse)