9mm, 0.37g At the time, and considering the fact that it was sold within the UK, I just assumed that it would be something like a Durotriges minim and a quick search would find a match. I've now devoted hours of time to searching through collections of Celtic coins and I have not managed to find anything even remotely resembling it. The cup shape has also ensured that one face of the coin is practically obliterated, which doesn't help matters. Is it a bad attempt at a counterfeit coin from the Celts? Something else entirely, and I'm on the wrong continent? Any comments would be most welcome, and feel free to share any of your own mystery coins.