Countermark

https://rpc.ashmus.ox.ac.uk/countermark/731 
GIC 605
monogram ΑΠ (on obverse or reverse)
square 
7 mm 
Ap(ollonia?) 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC VI, 4170 (temporary) Show 3567 2 6
RPC VI, 4171 (temporary) Show 3566 1 6
RPC VIII, — (number not assigned), type ID 20091 Show 963 1 8