Watch List notes:

Constantius II caesar, 324 – 327. Semissis, Siscia 337-340, AV 2.28 g. CONSTANTIVS PF AVG Rosette diademed, draped and cuirassed bust r. Rev. OB VICTORIAM TRIVMPHALEM Two Victories standing facing one another, holding between themselves a wreath inscribed VOT XV. C –, cf. 148 (solidus). Mazzini 148 (this coin). RIC 126. Biaggi 2154 (this coin). Depeyrot 9/3 (this coin).
Of the highest rarity, only the second specimen known. Extremely fine

Ex Sotheby's 6 June 1921, 148; Ars Classica XVII, 1934, Evans, 1936; Münzhandlung Basel sale 6, 1936, 2034 and NGSA sale 8, 2014, 158 sales. From the Mazzini and Biaggi collections.