https://rpc.ashmus.ox.ac.uk/countermark/321 

GIC 194

gorgoneion? facing

incuse square 

6 x 6 mm 

Rhosus (Cilicia)

P. Seyrig 76 coin of Claudius with GIC 342. GIC notes that the face might represent Zeus/Hada rather than a gorgoneion, which would be appropriate for Rhosus (Butcher)