Graffiti is quite normal on
Roman Republican coins (and perhaps on all
ancient coins). I don't know the reason. It might be as simple as a couple of soldiers in a
bar scratching their names when drunk. I don't think it was intended as a formal
counter-mark such as banker or nummularius stamps. It's as relevant perhaps as a ballpoint pen scrawl on a 20 pound note, i.e. less relevant for informing us on monetary policy but perhaps quite relevant as regards social life. There are many reasons that people write on bank-notes so thinking of the ancient analogy might spark some interesting thoughts.
