Countermark

https://rpc.ashmus.ox.ac.uk/countermark/726 
GIC 600
PRO (possibly PRC?)
rectangular 
3.5–5.5 × 6.5–11 mm 
 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 4277 Show 4277 13 1
RPC I, 4297 Show 4297 22 1
RPC I, 4264 Show 4264 21 1
RPC I, 4277 Show 4277 24 1
RPC I, 4277 Show 4277 26 1