Countermark

https://rpc.ashmus.ox.ac.uk/countermark/761 
GIC 638
monogram ΤΟ ΚΡΑ
circular 
6–6.5 mm 
ΤΟ ΚΡΑ = year 121 = AD 243/4. GIC gave BMC 239 as having GIC 638, Reassigned to GIC 631; on reverse 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC VI, 5652 (temporary) Show 5284 2 6
RPC VI, 5501 (temporary) Show 5103 19 6
RPC V.2, — (number not assigned), type ID 65 Show 4978 1 5.2
RPC V.2, — (number not assigned), type ID 587 Show 4970 2 5.2
RPC VI, 5501 (temporary) Show 5103 18 6
RPC V.2, — (number not assigned), type ID 1187 Show 4979 9 5.2
RPC V.2, — (number not assigned), type ID 1187 Show 4979 4 5.2
RPC V.2, — (number not assigned), type ID 71822 Show 4900 1 5.2
RPC V.2, — (number not assigned), type ID 1070 Show 4939 1 5.2
RPC V.2, — (number not assigned), type ID 167 Show 4964 1 5.2
RPC V.2, — (number not assigned), type ID 89067 Show 5001 1 5.2
RPC V.2, — (number not assigned), type ID 1223 Show 5005 8 5.2
RPC V.2, — (number not assigned), type ID 295 Show 5007 2 5.2