https://rpc.ashmus.ox.ac.uk/countermark/352 

GIC 230

Artemis the huntress standing r., drawing arrow, holding bow, in a dotted circle (on reverse)

circular 

7 mm 

Chersonesus (Bosporus)

On reverse. The cmk represents the chief deity of Chersonesus. The mint only issued small volumes of bronze under Trajan and none under Hadrian. The countermarking may have enabled the worn Flavian coins to continue in circulation.