I recently bought this Galerius follis which was misdescribed as a Maximianus: 28-26 mm. 9.66 grams. Yes, the legend says "MAXIMIANVS" but that was also the name of the emperor we call Galerius. They had very similar names in Roman times, but we distinguish them clearly in modern times. One was M. Aurelius Valerius Maximianus and the other C. Galerius Valerius Maximianus. The emperor we know as Maximianus was made Augustus by Diocletian without passing through the lower rank of Caesar. Any coin of "MAXIMIANVS" that continues on to say Caesar is necessarily of Galerius. By the way, the emperor we call "Maximinus II" was C. Galerius Valerius Maximinus, only one letter different from Galerius. This coin is from Trier, RIC 594b, dated to c.303 - 1 May 305 (after which Galerius was Augustus and not Caesar).
Nice one. I am actually a little into these coins, since this is the period in which I find what I call "art deco" obverse styles. Just on some of them, neither of which are pictured, but the very abstract type portraits I love to pick up when I can.
We really would have been better off if historians had decided to call Galerius Maximianus II but I suppose that would have just thrown more of the problem on people not separating him from Maximinus II (the guy shown on Randy's second coin). You really do need to read every letter on these things and avoid making assumptions. I have a page that might help: http://www.forumancientcoins.com/dougsmith/max.html Through Roman history there are several people who recycled names for their sons to the added confusion of coin collectors. It is a little sad that we have professional dealers who can't keep these straight.
every now and then i'll run across an elagablus on ebay listed as an antonius pius because of the legend...thankfully they look absolutely nothing alike on the coins, so a rookie mistake for sure. i still get mixed up on gallerius/maximanus....