Sorry to be so late, but here is my example of the coin AA led off the thread with. To my eye they are from the same dies.
Bing, your Severus piece is really nice. I debated about putting up one of those but now I'm glad I held off because your's is nicer. Nonetheless, let me follow it up with a couple more from that Severan series, also from Anchialus. An AE27 (11.73g) was struck for Caracalla in that series, with three looping arches instead of four. The coins for father and son were both pentassaria. But now it really gets interesting. Not to be outdone, Geta was featured on a (dekassaria?) AE29 (13.06) in which a rather animated figure (of Geta?) is perched atop the gate between two looping arches. To my knowledge this coin is presently unpublished, so I ask that the image not circulate. This motif was resurrected after the dynasty by Gordian III. The coin below is an AE29 but weighs a whopping 21.22g. The reverse motif is like that of Geta, but the figure atop the gate is advancing in the opposite direction. Since it too was produced at the provincial mint at Anchialus, I consider it to be from the same series as the Severans.
@AA did you want to continue comparing notes on these? I have another half dozen or so for Anchialos. Will not be near a computer tomorrow, but will be back. Let me know your pleasure.
It would be great to see the rest of your collection but post at your leisure, being retired now I tend to get on CT all hours of the day. Thanks for your input you have some fantastic coins.