Watch List notes:

Constantius II Siliqua Overstruck on Denarius of Caracalla. Siliqua; Constantius II Siliqua Overstruck on Denarius of Caracalla; 337-361 AD, Siscia, 351-355 AD, Siliqua, 2.91g. Cf. RIC-324 (R). Overstruck types: Obv: D N CONST[AN - TIVS P F AVG], Pearl-diademed, draped, cuirassed bust of Constantius II r.; Rx: VOT / XXX / MVLT / XXXX in wreath, [SIS] in exergue. Understruck types: Obv: [ANTONINVS - [P]IVS AVG, profile of unbearded Caracalla r.; Rx: [P]ONTIF [T]R P..., the continuation of Caracalla's titles having been destroyed by the overstrike. The busts of the two emperors are fairly close and nearly parallel to each other, so as to almost give the impression of a jugate portrait. Constantius II's overstruck mintmark will have been SIS for Siscia, since according to RIC only Siscia used the abbreviations VOT and MVLT in this type, instead of VOTIS and MVLTIS. A remarkable and possibly unique overstrike, all four of whose dies were apparently official, though Kent's relevant RIC VIII volume mentions no parallel cases that we can find of siliquae of Constantius II being overstruck on silver denarii that had originally been issued about 150 years earlier.A most unusual coin, where a siliqua was overstruck on a denarius, with the portrait of Caracalla clearly visible. aEF