Helena, mother of Constantine I, first wife of Constantius I
 (born ca. 248 A.D. - died 330 A.D.)
-  AE3 - 17.85mm, 2.92g
Obverse - FL HELENA AVGVSTA
Helena, her pearl-diademed and mantled bust right,
wearing necklace.
Reverse - SECURITAS REIPVBLICE
SMKA dot in Exergue
Securitas (or Helena) standing left, lowering branch,
raising robe with right hand.
Minted at the 1st officina in Cyzicus (Balkiz, Turkey) between 325 and 326 A.D.

Reference:
Bruun, P.M., "Roman Imperial Coinage", Volume 7 (RIC), Cyzicus, p649, nr 39, obverse legend 12, bust E10
Failmezger, V., "Roman Bronze Coins From Paganism To Christianity 294-364 A.D." (Fm), nr 357H
Carson, R.A.G., Hill, P.V., & Kent, J.P.C., "Late Roman Bronze Coinage" (LRBC),  Part I, p28, nr 1194
Sear, D.R., "Roman Coins and their Values" (Sear RCV 4th Revised Ed.), p329, nr. 3908, var with SMKA dot mint mark.
Sear, D.R., "Roman Coins and their Values" (Sear RCV Millennium Ed.), Volume 4, p516, nr 16624
Suarez, R., "Encyclopedia of Roman Imperial Coins II" (ERIC2),  p887, nr.47 (B1, O1, R3, T3, M5, SMKAdot)
Suarez, R., "Encyclopedia of Roman Imperial Coins II" (ERIC II-digital), p733, nr.47 (B1, O1, R3, T3, M5, SMKAdot)
Van Meter, D., "Handbook of Roman Imperial Coins" (VM), p293, nr 3, reverse legend variety
Kampmann, U., "Die Münzen der römischen Kaiserzeit" (K, 2e Auflage), p426, nr. 139.4.

Quality: Very Fine
Rarity:  C (Common)