Countermark

https://rpc.ashmus.ox.ac.uk/countermark/948 
GIC 833
denominational mark Ι
circular or oval 
6 - 6.5 mm 
Uncertain of Bithynia (Bithynia)
Two punches oval, one circular - either Nicaea or Nicomedia 
List of countermarks View on a map

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC VII.2, 1892 Show 1892 1 7.2
RPC VII.2, 2000 Show 2000 2 7.2
RPC IV, 10642 (temporary) Show 3449 1 4.1
RPC VII.2, 1986 Show 1986 3 7.2
RPC VII.2, 1984 Show 1984 3 7.2