Countermark

https://rpc.ashmus.ox.ac.uk/countermark/1329 
GIC
MT or MOT in monogram?
square or rectangular 
4.5 mm 
 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC III, 1148E Show 1148 4 3
RPC III, 1160 Show 1160 2 3