Constantine I, AE follis. Ticinum. AD 316. 

IMP CONSTANTINVS AVG, laureate, cuirassed bust right.
MARTI CONSERVATORI, Mars standing right, helmeted, in 
military dress, cloak over right shoulder, holding 
upright spear, point downwards and resting left hand 
on shield.

Star in left field, cross in right field.
Mintmark PT or TT. 

RIC VII Ticinum 47.
Rated R5.

Contributed by Richard Demarco of Carpe Diem Numismatics