I agree that it looks like SNM. Tesorillo is a great place to help identify these coins. For this one:
Constantinus Magnus and sons Constantinus II, Constans, and Constantius II. I don't know if you can narrow these coins down to a more specific issuing ruler, but perhaps someone else on the board might know better.
http://www.tesorillo.com/aes/112/112i.htm
Constantinus Magnus and sons Constantinus II, Constans, and Constantius II. I don't know if you can narrow these coins down to a more specific issuing ruler, but perhaps someone else on the board might know better.
http://www.tesorillo.com/aes/112/112i.htm

























