Bronze, 2.61 grams, 19.37 mm. Trier. 316 AD. Obverse: CONSTANTINVS PF AVG, laureate and cuirassed bust right. Reverse: MARTI CON-SERVATORI, Mars, helmeted, in military dress, cloak spread, standing right, holding reversed spear, left hand resting on shield; T-F across fields, mintmark BTR in exergue. Unlisted bust type for the series with this obverse legend and mintmark. RIC VII Trier 113 var; Sear -. Good very fine. A significant coin which has been published on wildwinds.com