it's a certificate of authenticity, not certificate of attribution though...that's a completely different set of paperwork
[ATTACH] Maximianus A.D. 292- 293 Ӕ Antoninianus 21x23mm 3.1g IMP MAXIMIANVS AVG; radiate helmet and cuirassed bust right PAX AVGG; Minerva...
Years ago, I made a little chart that shows the contrary nature of Rome. I did not include Sirmium on the chart as they did not issue any of the...
officina and workshop are the same thing. the example from Wildwinds looks like the third workshop-- Γ (gamma)
despite the unusual obverse legend of FL CONSTANTIS BEA C, your coin is Constans. at this time, Siscia operated five workshops-- A, B Γ Δ and Є...
You can get rust on bronze coins as the alloys can contain trace amounts of iron, sometimes enough for the coin to be slightly magnetic. I have a...
No, I have not seen it, but figured it might be of interest.
https://www.ma-shops.com/jacquier/item.php?id=520
If you do not already know it, or have a reference book, you can always look up names of Emperors online....
two (possibly) helpful links http://www.gallic-empire.com/coinage.htm http://www.forumancientcoins.com/lateromancoinage/gallic/postumus.html
Though RIC VI gives A.D. 310- 312 range for this type, it should probably be 311- 312. Constantine is gearing up for his war against Maxentius...
it's Gratian
a couple of years ago, I won this coin for a few dollars (felt a little guilty)...seller's original pic-- [ATTACH]
Separate names with a comma.
