I went to wildwinds to look this one up and it seems there are a few different variants of this one. I am not seeing the difference. Can any one help me on it. Looks to be a Maximianus RIC V 398 or 399 and both 398 and 399 have variants.
What I have found with some ancient Roman pieces is that you can find pieces that are very similar to what you have with the same words, emperor and god or personification, but something will be different. This is far more true for the Sears books, which don’t list a lot a coins, and to a lesser extent, “Wild Winds.” The reason is the all of these dies were handmade and therefore subject to small differences in the positioning of the lettering, a spear, globe, arm or whatever. It makes it harder to attribute coins, and it can be concerning that what you have is genuine. I am still a novice and think I know what the real thing looks like, but I am far from an expert. That’s why I only buy from the dealers who have professional credentials. From what I’ve heard the dealers who belong to the International Association of Professional Numismatists have a higher code of ethics that the dealers who belong to the ANA and the PNG. Maybe I’m wrong, but that’s my perception
Maximianus Herculius Obv:– IMP MAXIMIANVS AVG, Radiate bust left in imperial mantle, holding sceptre surmounted by eagle Rev:– PAX AVGG Pax standing left, with Victory on globe and scepter Minted in Lugdunum (B in exe.). Emission 7, Officina 2. Spring A.D. 290 A.D. 291 References:– RIC V Part 2 399 Bust Type H (S). Bastien Volume VII 387 Similar to mine
It takes a while for collectors new to ancients to understand all the differences in coins caused by dies being individually cut rather than hubbed or mechanically reproduced. maridvnvm correctly used 'similar' in this case. Specialists might note the difference in the chest decoration while most of us would lump both together as one coin. I do not have a Pax in this group but look at my Salus with obverse chest decor medallion (three dots in circle flanked by dots in the four corners) compared to the OP 5 dot version. This is an optional feature of most/all ancients. We have to decide what we mean when we say something is the same or different. To well over half of collectors (the one coin per ruler crowd) all coins of Maximianus are the same. I don't recall meeting anyone who collected chest medallion varieties but I did know a student of laurel tie dots. This is a hobby that we customise to our own requirements.
I know a collector who collects the various shield decorations on busts of Probus which goes beyond my interests there. But then I collect examples with differing legends breaks in some areas of my collection. Very much each to their own.
The difference between 398 and 399 is the obverse inscription. Here are the listings: 398 has obverse inscription 9, with two varieties of bust types and a bunch of different marks in the exergue. 399 has obverse inscription 10, with three varieties of bust and even more marks in the exergue. Here is the table of obverse inscriptions: Yours, like a good swimming pool, doesn't have a P in it, so it's obverse legend 10, and therefore RIC 399.
@bcuda RIC is organized by obverse legend first then bust type, then reverse legend type and mintmark/officina marks. A weakness of RIC is that it presumes that you know the mint the coin was struck in before letting you sort down to the number type using the items above. So in order to properly ID your coin using Wildwinds, which organizes like RIC, is to follow the same pattern in identifying your coin. Major references use the same pieces of information from a coin to identify it and more specialized books will use further information to further classify coins. Like @dougsmit and @maridvnvm said above, there are additional details (cuirass designs, shield decorations, helmet styles, etc.) that only specialists will know and care about and use those more detailed references. You get to decide how specialized you want to be.