Countermark

https://rpc.ashmus.ox.ac.uk/countermark/77 
GIC 790
denominational mark Δ
square 
variable 
The coins lack homogeneity of size and style of the countermark. It is unlikely that they were countermarked at the same time. 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC IX, 486 Show 486 1 9
RPC IX, 508 Show 508 1 9
RPC VII.1, 53 Show 53 6 7.1
RPC VIII, — (number not assigned), type ID 20127 Show 931 2 8
RPC VIII, — (number not assigned), type ID 20182 Show 1113 5 8
RPC VI, 4014 (temporary) Show 3397 15 6
RPC X, — (number not assigned), type ID 62050 Show 1321 5 10
RPC X, — (number not assigned), type ID 63966 Show 1184 36 10