Countermark

https://rpc.ashmus.ox.ac.uk/countermark/771 
GIC 648
monogram EI?
square 
6 x 6 mm 
EI? 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 1128 Show 1128 3 1
RPC I, 1217 Show 1217 30 1
Show 255