Silver or bronze Roman Radiate [решено]

Hi does anyone know if this is a Roman Radiate? If so were there silver ones in such poor condition? Or maybe this is a debased one? The brown markings will come off but I don't see the point it's in that bad condition. Also who is the portrait of (I have bronze radiates that are the same)? It's 20mm in diameter. Thanks.

Late 3rd century antoninianus, by that time the coins were usually just silver plated and the ratio of silver to copper used in them was around 5% so it's no wonder that there isn't any silver left on such a worn example. I doubt this coin can be correctly identified off the portrait alone, at least part of the obverse legend is needed to identify the emperor and I can't see anything on the reverse to identify the mint.

Thanks for the info again. I managed to see more detail on the reverse (I think there's a little more silver in the coin than the pic suggests). I agree I think it's too worn to ID but I'm still quite happy as it's the only example I have.