Constantine I AE Half Follis. Rome. AD 312-313. 17 mm, 2.13 g

FL VAL CONSTANTINVS AVG, laureate, draped and cuirassed bust right, seen from the back.
PACI PERPET, Pax standing left, holding branch and standard.

XII in left field.
Mintmark RP. 

RIC VI Rome 358.

With permission of Leu Numismatik AG - Web Auction 26, Lot 5254, July 2023.
Ex L. Ramskold, ex Leu Auction 7, lot 1386, Feb. 2019.