It took me a couple days but I'm closing out the attributions on this lot: Constantine II; 326-28 AD Bronze AE3, 20mm/3.7g, Thessalonica mint OBV: CONSTANTINVS IVN NOB C, head, laureate, draped & cuirassed bust left / REVROVIDENTIAE CAESS, camp-gate with two turrets and star above, SMTS in ex. (RIC VII 157.1)
Constantine I; 320-321 AD Bronze AE3; Siscia Mint; 19mm/3.1g OBV: CONSTANTINVS AVG, laureate head right REV: DN CONSTANTINI MAX AVG, VOT XX in wreath, SIS star in ex (RIC VII, 159b)
Still rasslin' with this one. Constantine I; Bronze AE3; 21mm/2.8g OBV: IMP CONSTANTINVS P F AVG; Head, laureate, and draped right REV: IOVI CONSERVATORI; Jupiter standing left, holding Victory on a globe & sceptre, eagle with wreath in beak at foot, ST(gamma?) in ex
You probably already know this, but SMTS is the Thessalonica mint, SM = Sacra Moneta, TS = Thessalonica. And it looks like you've got a dot, or some other control mark on the Constantine I VOT mint mark: dot, SIS, star.
I think you mean TS, which is also Thessalonica, and yes, it is a gamma, signifying the third officina. They didn't always include SM in the mint marks.
You might have solved the riddle for me JA. If it's dot TS dot Gamma dot. Then it would attribute as RIC VII, 19 I can't really tell if there are dots in between the mint mark letters though.
I was referring to the coin in post 45 in my last comment. All I see there is TS gamma. There may be dots, but the surface is kind of rough and it's hard to tell.