Watch List notes:

Claudius (41-54). AE Sestertius, 41-50 AD. PROB countermark on obverse. Obv. TI CLAVDIVS CAESAR AVG P M TR P IMP. Laureate head right. Rev. SPES AVGVSTA SC (in exergue). Spes advancing left, holding flower and raising skirt. RIC 99. AE. g. 21.12 mm. 35.50 F. Interesting and clear PROB(atum) countermark, apparently a mark of validation (see C. Kraay, 'The Behaviour of Early Imperial Countermarks,' Essays Mattingly, pp. 130-131).