Countermark

https://rpc.ashmus.ox.ac.uk/countermark/1373 
GIC
star (or rosette)
circular 
4 - 4.5 mm 
This cmk is similar to GIC 434, It is separated due to the western Greek origin of the coins from Zacynthus, and a presumed Pontic origin for the coins attributed to Augustus of "Coinage with Q" 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 5409 Show 5409 76 1
RPC I, 5410 Show 5410 15 1
RPC I, 5410 Show 5410 17 1
RPC I, 5410 Show 5410 19 1
RPC I, 5410 Show 5410 33 1
RPC I, 5410 Show 5410 34 1