I do not know but others will. Be sure and show the finished product. Great looking large coin, I like em a lot.
It looks like Galerius with an obverse of IMP C GAL VAL MAXIMIANVS PF AVG reverse of GENIO POPVLI ROMANI. I can't really make out the exergue; but probably Cyzicus mint...KA KB etc.
Thanks for the leads. There is a lot of crud over the exergue that I am removing a bit at the time. It will take a while to remove without damage.
There is only one with a star in the right field. I think this is a match. Galerius AE Follis. 307 AD. IMP C GAL VAL MAXIMIANVS PF AVG, laureate head right / GENIO POPVLI ROMANI, Genius standing left, holding Victory and sceptre, star in right field, mintmark KB. Thanks again. Dave
Here is the final, however, I reserve the right to do some touch up. I think I was able to maintain all the original detail in this one.