Constantine I, AE follis, London. AD 312-313. 22mm, 3.2 g.

CONSTANTINVS AVG, laureate bust left, wearing imperial mantle, holding eagle-tipped sceptre
MARTI CONSERVATORI, Mars standing right in military attire, 
holding reversed spear, left hand on shield.
Star in left field.
Mintmark PLN.

Huvelin 173; RIC VI London 260-261 var (bust type).

Contributed by ebay seller buy_yourself_a_coin, Nov. 2016.