Here is a recent addition - a solidus of Theodosius I (379-395 AD). Solidus (Gold, 21 mm, 4.46 g, 12 h), uncertain military mint, 393-395. D N THEODO-SIVS P F AVG Pearl-diademed, draped and cuirassed bust of Theodosius I to right. Rev. VICTORI-A AVGGG A / S - M / COMOB Theodosius I standing front, head to right, holding labarum in his right hand and Victory on globe in his left and placing his left foot on captive below. Depeyrot 34/5 corr. ('Sirmium', but misattributed to Theodosius II). RIC 15a.1 ('Sirmium'). The auction description says "uncertain military mint". That raises a few questions for me: 1. The reverse has S - M on Theodosius' sides. I first thought it was a mint mark for "Sirmium" as it was mentioned in the auction description. Sirmium was a city in the Roman province of Pannonia, located on the Sava river, on the site of modern Sremska Mitrovica in northern Serbia [Source: Wikipedia]. I have come to understood that S - M actually means "Sacra Moneta" - i.e. sacred money and thus not a mark for place of mintage. 2. Like other late Roman solidi the mint mark COMOB is in exergue abbreviating Comitatus Obryziacum or Constantinople solidus that has been struck at a weight of 72 to a pound. I am sure there is a longer history to this, but have understood that COMOB was also an earlier mintmark in itself. 3. What potential military mints could this coin have been minted at? I know Theodosius fought several campaigns agains the Goths and it has been indicated to have been minted at the very end of his reign and life, 393-395. He also died in Milan in 395. I would appreciate any comments or supplements to my somewhat confusion about the mintmark and any comments on the coin in general. Thanks!