Countermark

https://rpc.ashmus.ox.ac.uk/countermark/479 
GIC 359
murex shell
oval 
5 x 4 mm 
The differently shaped punch and earlier date indicate a different group from GIC 360. 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 4718 Show 4718 2 1