Countermark

https://rpc.ashmus.ox.ac.uk/countermark/514 
GIC 394
cap of Dioscuri
rectangular 
5 x 4 mm 
The Dioscuri were the dominant type at Tripolis. The coins of Patras are illustrative of the large movement of coin from the Peloponnese to Syria under Caracalla 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC V.3, — (number not assigned), type ID 69261 Show 5004 3 5.3
RPC V.3, — (number not assigned), type ID 69261 Show 5004 18 5.3
RPC V.3, — (number not assigned), type ID 69158 Show 5005 3 5.3
RPC V.3, — (number not assigned), type ID 69158 Show 5005 6 5.3
RPC V.3, — (number not assigned), type ID 69296 Show 5019 5 5.3
RPC V.3, — (number not assigned), type ID 69294 Show 5010 3 5.3