Countermark

https://rpc.ashmus.ox.ac.uk/countermark/1567 
GIC
lyre
circular 
4.5 mm 
on reverse 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 2823B Show 2823 1 1
RPC I, 2823B Show 2823 2 1
RPC I, 2823B Show 2823 3 1
RPC I, 2823B Show 2823 4 1