I think this its also silver because under dirt coin was shining.It's Hard recognize him still don't know how will clean him.It's look like roman coin? I only wash him with distillation water 6g 27mm
You can see letters DIOCLETI then could it be Diocletianus. But which coin have this dimension 6g 27mm and it's look like silver?
I would agree that it is Diocletian. At 27mm it is most likely an AE Follis. I can see a Gamma in the right field on the reverse. I'm not saying it is this coin, but perhaps something like it: http://wildwinds.com/coins/ric/diocletian/_trier_RIC_VI_0171a.jpg
