Good morning, I came across this in my "I have no clue how to attribute" bag and was hoping to get some more info on these. This isn't a great version of a monogram coin, but I would be interested to see others'. From the little bit of research I've done, these are mostly 5-6th century? For this one, it looks like Epsilon and kappa (or kai)? and is 14mm wide. edited
My quick guess: Justin II, AE Pentanummium. Cyzicus. Monogram (Sear type 8) / Large epsilon, K to right. SB 375, DOC 137.
Yes, http://www.catbikes.ch/coinstuff/coins-ric.htm, scroll scroll scroll to the Monograms section and click to download Dane's spreadsheet or click the link to illustrations.
Another option, old thread on Forum with lots of work done by Kevin ( Pep) SBCV Monogram Table Index (forumancientcoins.com)