Roman Imperial Coins – Augustus – Bull Denarius 11-10 BC.
Obv: AVGVSTVS DIVI F legend with laureate head right.
Rev: IMP XII legend beneath bull butting right. RIC 187a; RSC 155 BMC 474. 3.72 grams.
The census ordered by Roman emperor Augustus was for the purpose of taxation Joseph would have paid two silver denarii, like this coin