Countermark

https://rpc.ashmus.ox.ac.uk/countermark/708 
GIC 582
ϹΑΓ
rectangular 
6 x 3 mm 
GIC gave CAI (possibly ϹΑΓ), but further examples give CΑΓ as more likely. GIC also gave "possibly the same letters as GIC 581, but with the last two not ligatured". with ϹΑΓ as an optional reading. These were in the "Two or more Latin letters" section, but, with the Γ should be moved to the "Two or more Greek letters" section 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC V.3, — (number not assigned), type ID 68447 Show 3987 10 5.3
RPC V.3, — (number not assigned), type ID 68447 Show 3987 9 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 8 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 16 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 17 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 19 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 21 5.3
RPC V.3, — (number not assigned), type ID 68455 Show 3993 8 5.3
RPC V.3, — (number not assigned), type ID 68455 Show 3993 6 5.3
RPC V.3, — (number not assigned), type ID 68459 Show 3996 2 5.3
RPC V.3, — (number not assigned), type ID 68459 Show 3996 3 5.3
RPC V.3, — (number not assigned), type ID 68450 Show 4000 4 5.3
RPC V.3, — (number not assigned), type ID 68450 Show 4000 5 5.3
RPC V.3, — (number not assigned), type ID 68446 Show 3989 11 5.3
RPC V.3, — (number not assigned), type ID 78198 Show 3999 3 5.3
RPC V.3, — (number not assigned), type ID 68455 Show 3993 5 5.3
RPC V.3, — (number not assigned), type ID 78198 Show 3999 1 5.3