Thank you Joe for taking a look.
This is my first coin that shows two different cities from being
overstruck, and I think this is an extremely cool feature.
I have done a little research now and I've found out that these coins showing
Heraclius and
Heraclius Constantine are often
overstruck.
However looking at
plenty of pictures I have only found a few with a letter or two showing of the previous
mint mark, nothing like on my coin
Taking a liking for these I was fortunate enough to just win another one, this next specimen is a
Constantinople follis overstruck on a
Nicomedia follis with clear CON and NIKO! I will post a
thread in the general ancient coin board soon with both coins, hoping that others will post more.