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 1218 11 5.3
RPC V.3, — (number not assigned), type ID 72212 Show 1209 1 5.3
RPC V.3, — (number not assigned), type ID 72258 Show 1243 1 5.3
RPC V.3, — (number not assigned), type ID 72638 Show 1106 1 5.3
RPC V.3, — (number not assigned), type ID 72712 Show 1197 1 5.3
RPC V.3, — (number not assigned), type ID 72898 Show 1137 1 5.3
RPC V.3, — (number not assigned), type ID 73365 Show 1447 2 5.3
RPC V.3, — (number not assigned), type ID 73369 Show 1420 1 5.3
RPC V.3, — (number not assigned), type ID 73343 Show 1440 1 5.3
RPC V.3, — (number not assigned), type ID 72729 Show 1140 2 5.3
RPC V.3, — (number not assigned), type ID 92797 Show 1148 1 5.3
RPC V.3, — (number not assigned), type ID 72115 Show 1051 2 5.3
RPC V.3, — (number not assigned), type ID 95106 Show 1405 1 5.3