Agreed, the M should indicate a Byzantine follis (40 nummi). I don't have enough experience in this area to identify it by sight, but you can look for a match here if you wish
http://www.wildwinds.com/coins/sb/i.html
Or maybe another member more expert in this area will be able to identify it specifically.
http://www.wildwinds.com/coins/sb/i.html
Or maybe another member more expert in this area will be able to identify it specifically.






















