So thus is my first ancient coin. Constantine the great. 330ish AD. Iam really not sure. Iam gunna be doing research tonight. But here it is.
When I read your title I thought.. What's is an anicent? I thought it was a new type of coin I never heard of before.. An Ani-Cent.. But now I realized you meant ancient
Welcome to the Dark Side junior. A good couple of good references for LRBs: https://www.tesorillo.com/aes/home.htm - good for ID'ing help starting with reverse designs. http://www.wildwinds.com/ - great for all sorts of ancients. Not just LRBs.
I use Tesorillo to narrow down an emperor, and then Wildwinds to go the rest of the way. Btw it looks like Valentinian to me as well
According to Wildwinds this looks like a RIC 7a Type VII http://www.wildwinds.com/coins/ric/valentinian_I/t.html
Looks slightly different - your reverse is ASISC while his is DASISC Also yours has a P in the reverse left field, while his has an A.
Welcome to ancients - they are a lot of fun, and sometimes a bit frustrating to figure out. I'd agree that's Valentinian. I have a similar - but not identical one - from the same mint. Mine lacks the reverse field stuff, and has a dot before the Delta. Valentinian I Æ 3 (Æ 19) (367-375 A.D.) Siscia mint DN VALENTINIANVS PF AVG diademed draped and cuirassed bust right / SECVRITAS REIPVBLICAE, Victory walking left, holding wreath & palm. dot ΔSISC. RIC IX Siscia 7a, type ii. (2.31 grams / 19 mm)