I believe this coin to be one of (the many) Constantine I (The Great). I believe that we have an obverse legend of CONSTANTI_NVS MAX AVG around a rosette and diademed draped and cuirassed bust of Constantine, facing right. On the reverse, I believe that we have two soldiers with spears and shields and two standards (with dots on) facing each other. The mintmark appears to be 'off-flan' but there does appear to be an 'M' at the base of the standards between the soldiers. Is this the mintmark, or part of the mintmark, or an officina letter? Does this assist in determining the mint? Any thoughts will help, thank-you. Perhaps it is not an 'M'? (In hand it looks like one.)
I don't know TC, I don't think it's really there. Kind of looks like where the dirt is thinner combined with part of the standard. Sometimes the standard have little "spurs" that stick off on them.
If you're interested in LBRs... this is the book you should have for these types of coins. It can be ordered for around $20 for a softcover and $40 for a hardcover... and worth every penny. Anyway... I'm not sure how much it helps with this particular coin but it provides some leads. I'd post a photo of the GLORIA EXERCITVS page... but I know the forum's rules forbid it. Looking at the illustrated standard forms though... Rome and Cyzicus look to be the closest (and maybe 3rd, Constantinople). All mints have your obverse legend with a rosette diadem.
Yeah, there are a lot of great line illustrations detailing key style differences across mints so it's a good learning resource even if don't need it for identifying rough coins.
