These are called camp gates. I'm on my tablet and can't make out the legend. Here's an example of one of mine: Constantius II, AD 337-361. Æ Follis, 4g, 19mm, 12h; Cyzicus mint, 325-326. Obv.: FL IVL CONSTANTIVS NOB C; Laureate, draped, cuirassed bust left. Rev.: PROVIDEN-TIA CAESS; Campgate, two turrets, no doors, star above, eight stone layers // SMKS dot My advice is to hold off on buying these in the condition of the coin originally posted. They can be found in very nice condition for not very much money.
Google something like "Roman mint marks" and see if you can't find a list. Learning to attribute ancient coins is a lot of fun. If I tell you, I'll be denying you that learning experience.
Campgates are relatively common, but are nice to collect. Not too expensive. CONSTANTINE I AE3 Follis OBVERSE: CONSTANTINVS MAX AVG, diademed head right REVERSE: PROVIDENTIAE AVGG, campgate with two turrets & no doors, star above, GSISdouble-crescent in ex. Struck at Siscia 328-9 AD 3.3g, 19mm RIC VII 215G
You have mistakenly attached a coin of Constantine II or posted the wrong description for the the coin pictured. 215 though, is diademed, draped and cuirassed.
Yep. Copied the wrong description from my catalog. Sorry about that. It should read: CONSTANTINE II AE Follis OBVERSE: CONSTANTINVS IVN NOB C, laureate head right REVERSE: PROVIDENTIAE CAESS, campgate with two turrets, star above, eSIS(double crescent) in ex. Struck at Siscia 328-29 AD 2.9g, 20mm RIC VII 216 So here is the Constantine I CONSTANTINE I AE3 Follis OBVERSE: CONSTANTINVS MAX AVG, diademed head right REVERSE: PROVIDENTIAE AVGG, campgate with two turrets & no doors, star above, GSISdouble-crescent in ex. Struck at Siscia 328-9 AD 3.3g, 19mm RIC VII 215G
Thanks. That approach seems right. I do not collect romans, but when I get the opportunity to buy them cheap, I do not pass, because I love history and I love coins