Struck at Lyon, this Roman bronze coin has Constantine I on obverse and Sol on reverse. It weighs 2.65 g. with PLG in exergue. There are 2 letters T and N on each side of the 2 fields. I couldn't find any reference for these 2 letters across fields.
Yes @Cucumber. In fact, not only at hand with the magnifier, but also here's a close scan at very high resolution.
I'm stumped. The coin is in rough shape. It could be a preservation artifact or a mint error. There is no T-N series that I'm aware of.
Here's a much closer N. At hand it's even clearer than this. BTW.. what do the letters across fields represent ?
N makes no sense in this series. It must be an F. Compare it to the following examples (all are T-F).