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Constantine I AE3 "Vows XX" Constantine I "the Great" AD 306-337 AE3 
Obv: CONSTAN-TINVS AVG - Laureate head right. Rev: D N CONSTANTINI 
MAX AVG - Within wreath is written VOT XX; a (star) subscript and 
between them. Exe: (star) | SMHB Heraclea mint: AD 324 = RIC VII, 
60, page 549 - British Museum./ 3.10 g.