Countermark

https://rpc.ashmus.ox.ac.uk/countermark/1400 
GIC
IDG CXP in two lines
rectangular 
7 x 6 mm 
I(mperator) D(omitianus) G(ermanicus C(os) X P(robavit) - dated AD 84 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
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