Watch List notes:

Gallienus. AD 253-268. Antoninianus (21mm, 3.26 g, 5h). Dated consular issue. Mediolanum (Milan) mint. 4th emission, AD 262-263. IMP GALLIENVS AVG COS V, radiate bust left, wearing consular robe, holding eagle-tipped scepter / VIRTV S AVG, soldier standing left, holding shield set on ground to left and reversed spear. Cf. RIC V 114a (Rome); MIR 36, 1159dd1 (same dies as illustration); Toffanin 190/24; cf. RSC 1244; CNG E-442, lot 442 (hammer $425). Nearly full silvering, struck with worn reverse die, flan crack. VF. Extremely rare. Only one noted by MIR. Toffanin gives this issue RRRRR (della più grande rarità, i.e., "of the greatest rarity").