Countermark

https://rpc.ashmus.ox.ac.uk/countermark/843 
GIC 722
monogram ΤΙΚΔ
Sometimes on reverse 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 4775 Show 4775 1 1
RPC I, 4774 Show 4774 20 1
RPC I, 4774 Show 4774 22 1