Right-facing bust: [IMG] AE III Undetermined mint, A.D. 356-366 Obv: D N PROCO-PIVS P F AVG Rev: REPARATI-O FEL TEMP - Emperor standing, facing...
Verdicare is designed to remove verdigris from coins. I'm not sure it's a cure for bronze disease, though. Verdigris, which is also bluish-green,...
As far as I know, sodium sesquicarbonate will work, but it's nasty stuff, and I can't swear to its effectiveness because I've never had to resort...
Not what you asked for, but I wanted to point out that in addition to GPR legends, there are several other legends for the same reverse type and...
I'm stumped. The coin is in rough shape. It could be a preservation artifact or a mint error. There is no T-N series that I'm aware of.
[IMG] Silver Double Denarius Antioch mint, A.D. 253 Obv: IMP C P LIC VALERIANVS AVG Rev: PIETAS AVGG - Two emperors (Valerain I and Gallienus),...
It's possibly a partially filled die or just and engraver's error.
Separate names with a comma.
