Countermark

https://rpc.ashmus.ox.ac.uk/countermark/842 
GIC 721
AVII or IIVII
rectangular 
3.5 x 6.5 mm 
On obverse. For the variant IIVII - the initial II is likely a misshapen A 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC V.3, — (number not assigned), type ID 69998 Show 4371 1 5.3
RPC V.3, — (number not assigned), type ID 69968 Show 4370 3 5.3
RPC V.3, — (number not assigned), type ID 69951 Show 4372 2 5.3
RPC V.3, — (number not assigned), type ID 69997 Show 4374 1 5.3
RPC V.3, — (number not assigned), type ID 69959 Show 4376 7 5.3
RPC V.3, — (number not assigned), type ID 69959 Show 4376 8 5.3
RPC V.3, — (number not assigned), type ID 69979 Show 4392 2 5.3
RPC V.3, — (number not assigned), type ID 70000 Show 4391 2 5.3
RPC V.3, — (number not assigned), type ID 69963 Show 4395 1 5.3
RPC V.3, — (number not assigned), type ID 69974 Show 4396 1 5.3
RPC V.3, — (number not assigned), type ID 69959 Show 4376 3 5.3
RPC V.3, — (number not assigned), type ID 85558 Show 4378 1 5.3
RPC V.3, — (number not assigned), type ID 69951 Show 4372 13 5.3
RPC V.3, — (number not assigned), type ID 69951 Show 4372 7 5.3
RPC V.3, — (number not assigned), type ID 87076 Show 4383 1 5.3
RPC IV, 9129 (temporary) Show 2147 2 4.3
RPC IV, 9129 (temporary) Show 2147 2 4.3