This coin was struck on a rather thick flan with a diameter much smaller than the dies and the legends are largely off the flan: 2.67 g, 13.5 mm, 5 h. The obverse inscription reads ... -S NOB C, establishing it as issued by one of the junior rulers. The reverse legend appears to read SE ..., so it's probably a SECVRITAS REIPVBLICAE or maybe a SALVS REIPVBLICAE Victory advancing left type, though I suppose FELICITAS ROMANORVM is possible, too. It's clearly from Alexandria. I feel like I should be able to ID this, but I can't. Who is this?
I checked RIC XII, IX and X, and I can't find any obverse inscription ending -S NOB C for Alexandria.
I know; that's the freaky thing. And I don't think I'm imagining the NOB C or mistaking it for something else.
Barbarous/unofficial?? I'm out of my league here but the primary place I check for LRB identification is Tesorillo. The (presumably) Victory on your coin appears to be holding a palm branch in her left hand, although the hand is in the position seen with dragging a captive. I don't see anything like it on Tesorillo. Edited: maybe the dragged captive is off flan or otherwise obscured on this coin and maybe you're mistaken about the ...S NOB C legend?
I'm not as convinced that the obverse legend reads S NOB C. Looks like it could be just about anything to me... and I vote for PF AVG. Is there a captive on the reverse? Is the area I circled a captive or just distortion from time and wear? There seems to be a dot in the left field close to Victory, which fits with known marks for Alexandria in this SALVS REPVBLICAE type of "victory dragging captive). Per Tesorillo reverse type 135, it could be Theodosius I, Valentinian II, Arcadius, or Honorius.
To me this looks like a normal die for an early SECVRITAS REI-PVBLICAE printing on a dumpy flan that has way too little diameter for the die - which I think is how you see it too. That said, the era of production for these would be early Valentinian for a normally larger coin. Hence: Valentine I, Gratian, and Valens. I see that the right side obverse legend begins with S, but I agree with TIF that the reading is more likely S PF AVG, although the letters are arranged differently than she would have them. She has covered the S with a P, and what she is calling an F I read as the P. If I am correct, then after that P there are four more raised spots for letters - F A V G. That would make it Valens. RIC IX Alexandria 3b, officina Delta.
One of the things that has always griped me about RIC IX is that they define "periods" by chronology, rather than "series" by markings. The difference between period 1 and period 2 is that the second begins when Gratian is elevated to power. The listings seem to be saying that the coins of the other two continued to be produced unaltered after that happened. To put it into perspective, Volume IX was an early approach to the RIC series which was created to help slot coin material into historical categories. Later volumes altered the concept into a study of coin morphology set in an historical framework. A shift from WHO was on the coin to WHAT was on the coin. Both got covered in both evolved approaches, but in different ways.
That is right. If you look at this page you can see the historical events (elevations and deaths) that are endpoints to the RIC IX time periods. http://augustuscoins.com/ed/ricix/timeline.html If a type continued from one period to the next because of an event for emperor B, it will have two RIC IX numbers for emperor C even if the type and mintmark is completely unchanged from one to the other.