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 1682 6 10
RPC X, — (number not assigned), type ID 61345 Show 1682 5 10
RPC X, — (number not assigned), type ID 61345 Show 1682 1 10
RPC X, — (number not assigned), type ID 61345 Show 1682 2 10
RPC X, — (number not assigned), type ID 61346 Show 1681 1 10
RPC X, — (number not assigned), type ID 61347 Show 1712 4 10
RPC X, — (number not assigned), type ID 61348 Show 1713 6 10
RPC X, — (number not assigned), type ID 61348 Show 1713 4 10
RPC X, — (number not assigned), type ID 61348 Show 1713 3 10
RPC X, — (number not assigned), type ID 61350 Show 1710 1 10
RPC X, — (number not assigned), type ID 61352 Show 1711 11 10
RPC X, — (number not assigned), type ID 61352 Show 1711 3 10
RPC X, — (number not assigned), type ID 61357 Show 1717 5 10
RPC X, — (number not assigned), type ID 61357 Show 1717 9 10
RPC X, — (number not assigned), type ID 61357 Show 1717 10 10
RPC X, — (number not assigned), type ID 82877 Show 1719 2 10
RPC X, — (number not assigned), type ID 61358 Show 1725 3 10
RPC X, — (number not assigned), type ID 61358 Show 1725 4 10
RPC X, — (number not assigned), type ID 61358 Show 1725 2 10
RPC X, — (number not assigned), type ID 61358 Show 1725 7 10
RPC X, — (number not assigned), type ID 61358 Show 1725 13 10
RPC X, — (number not assigned), type ID 61362 Show 1723 5 10
RPC X, — (number not assigned), type ID 61363 Show 1726 1 10
RPC X, — (number not assigned), type ID 61363 Show 1726 4 10
RPC X, — (number not assigned), type ID 61519 Show 1622 12 10
RPC X, — (number not assigned), type ID 61345 Show 1682 10 10
RPC X, — (number not assigned), type ID 61345 Show 1682 14 10
RPC VI, 5352 (temporary) Show 4983 2 6