Countermark

https://rpc.ashmus.ox.ac.uk/countermark/66 
GIC 796
denominational mark Δ in circular punch
circular 
7 mm 
The origins of the coins and their size is consistent with the hypothesis that GIC 767 (Β), GIC 777 (Γ) and GIC 796 (Δ) were part of the same system (applied at the same place at the same time) 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC IX, 1000 Show 1000 2 9
RPC VII.1, 622.2 Show 622.2 14 7.1
RPC X, — (number not assigned), type ID 62165 Show 2729 2 10
RPC X, — (number not assigned), type ID 63383 Show 3269 1 10
RPC VIII, — (number not assigned), type ID 20802 Show 1948 2 8