I have a Constantine RIC VII 123(gamma), but the mintmark is (clearly) "N N (gamma)". According to 'R.I.C.' it should read 'M N (gamma)'. Is the attribution incorrect? Is it an 'error'? Is there another reason for this? I would like to know what you think. Can anyone help, please?
So finally, it's MN gamma struck at Nicomedia. The second vertical right bar of the letter M had been corroded or widened after so many centuries, possibly. PMD..
Thank-you, fellas. I shall enter the Mintmark as per catalogue "M.M." and delete my "N.M." Thank you again.
I agree that it is probably an engraver error. You might enter it as N[sic]N Gamma, cf. RIC 123 or something similar.