Countermark

https://rpc.ashmus.ox.ac.uk/countermark/233 
GIC 110
laureate head r.
circular 
7 mm 
Noted on coins of Ancyra (Galatia) and Pessinus, so possibly might have been applied at Pessinus? Possibly connected with Caracalla's journey to the east in 215. 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC V.3, — (number not assigned), type ID 72010 Show 1192 11 5.3
RPC V.3, — (number not assigned), type ID 72212 Show 1183 1 5.3
RPC V.3, — (number not assigned), type ID 72258 Show 1216 1 5.3
RPC V.3, — (number not assigned), type ID 72638 Show 1083 1 5.3
RPC V.3, — (number not assigned), type ID 72712 Show 1171 1 5.3
RPC V.3, — (number not assigned), type ID 72898 Show 1113 1 5.3
RPC V.3, — (number not assigned), type ID 73365 Show 1416 2 5.3
RPC V.3, — (number not assigned), type ID 73369 Show 1389 1 5.3
RPC V.3, — (number not assigned), type ID 73343 Show 1409 1 5.3
RPC V.3, — (number not assigned), type ID 72729 Show 1116 2 5.3
RPC V.3, — (number not assigned), type ID 92797 Show 1124 1 5.3
RPC V.3, — (number not assigned), type ID 72115 Show 1028 2 5.3
RPC V.3, — (number not assigned), type ID 95106 Show 1374 1 5.3