Countermark

https://rpc.ashmus.ox.ac.uk/countermark/928 
GIC 813
denominational mark Ϛ
circular 
6.5 mm 
Sometimes on reverse 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC X, — (number not assigned), type ID 61345 Show 1624 6 10
RPC X, — (number not assigned), type ID 61345 Show 1624 5 10
RPC X, — (number not assigned), type ID 61345 Show 1624 1 10
RPC X, — (number not assigned), type ID 61345 Show 1624 2 10
RPC X, — (number not assigned), type ID 61346 Show 1623 1 10
RPC X, — (number not assigned), type ID 61347 Show 1652 4 10
RPC X, — (number not assigned), type ID 61348 Show 1653 6 10
RPC X, — (number not assigned), type ID 61348 Show 1653 4 10
RPC X, — (number not assigned), type ID 61348 Show 1653 3 10
RPC X, — (number not assigned), type ID 61350 Show 1651 1 10
RPC X, — (number not assigned), type ID 61352 Show 1650 11 10
RPC X, — (number not assigned), type ID 61352 Show 1650 3 10
RPC X, — (number not assigned), type ID 61357 Show 1659 5 10
RPC X, — (number not assigned), type ID 61357 Show 1659 9 10
RPC X, — (number not assigned), type ID 61357 Show 1659 10 10
RPC X, — (number not assigned), type ID 82877 Show 1661 2 10
RPC X, — (number not assigned), type ID 61358 Show 1667 3 10
RPC X, — (number not assigned), type ID 61358 Show 1667 4 10
RPC X, — (number not assigned), type ID 61358 Show 1667 2 10
RPC X, — (number not assigned), type ID 61358 Show 1667 7 10
RPC X, — (number not assigned), type ID 61358 Show 1667 13 10
RPC X, — (number not assigned), type ID 61362 Show 1665 5 10
RPC X, — (number not assigned), type ID 61363 Show 1668 1 10
RPC X, — (number not assigned), type ID 61363 Show 1668 4 10
RPC X, — (number not assigned), type ID 61519 Show 1708 12 10
RPC X, — (number not assigned), type ID 61345 Show 1624 9 10
RPC X, — (number not assigned), type ID 61345 Show 1624 13 10