Constantine I, 307 - 337 AD
AE Follis, Treveri Mint, 24mm, 4.70 grams
Obverse: IMP CONSTANTINVS AVG, Laureate and cuirassed bust of Constantine right.
Reverse: MAETI CONSERVATORI, Mars standing right holding shield and spear, T P across fields, PTR in exergue.
RIC857 var P in field is either a celator error or a poorly rendered 'F'. "