Helena, mother of Constantine I, first wife of Constantius I
 (born ca. 248 A.D. - died 330 A.D.)
-  AE4 - 15.12mm, 1.25g
Obverse - FL IVL HE-LENAE AVG
Helena, her pearl-diademed and mantled bust right,
wearing necklace.
Reverse - PAX PVBLICA
TRP in Exergue
Pax standing left, holding branch and transverse scepter
Minted posthumously under Constantius II at officina P in Treveri (Trier, Germany) between 337 and April 340 A.D.

Reference:
Kent, J.P.C.,"Roman Imperial Coinage", Volume 8 (RIC), Trier, p144, nr 78, obverse H1/M.
Carson, R.A.G., Hill, P.V., & Kent, J.P.C., "Late Roman Bronze Coinage" (LRBC),  Part I,  p5, nr. 119, obv 6cW
Failmezger, V., "Roman Bronze Coins From Paganism To Christianity 294-364 A.D." (Fm), nr 384H
Sear, D.R., "Roman Coins and their Values" (Sear RCV Millennium Edition), Volume 5, p120, nr. 17492.
Suarez, R., "Encyclopedia of Roman Imperial Coins II" (ERIC2),  p888, nr.118-122 var TRP (B1, O2, R1, T1, M15, TRP)
Suarez, R., "Encyclopedia of Roman Imperial Coins II" (ERIC II-digital), p733, nr.118-122 var TRP (B1, O2, R1, T1, M15, TRP)
Van Meter, D., "Handbook of Roman Imperial Coins" (VM), p293, nr 4.
Kampmann, U., "Die Münzen der römischen Kaiserzeit", 2nd revised edition (Kampmann), p426, nr. 139.5.

Quality: Fine+
Rarity: C (Common)