Trial Or Error ? Another Lrb Oddity

I am inclined to join Broken Coin's camp.

what is the size of the coin ? For Gratian it has to be 12/13 mm , see RICIX,21,AES IV,smaller module.albert

Thanks for the replies folks,
Weight - 0.79g
Size - 13mm
It matches the Gratian AE4 issue as suggested by Albert.
I went through all the possible emperors and after various reasons for elimination I was left with Gratian.
I didn't want to call it a brockage because the Obverse is blank, its normally got an image from what I have seen

For a 13mm module from Cyzicus, nothing in RIC VIII is small enough. I read it as officina gamma, but the pics are not big enough for these old peepers. But whether B or gamma, the options for the obverse are Gratian, Valentinian II, and Theodosius. Nor can we rule out Arcadius since the only example listed in RIC XI for him has an obscured officina mark.

But for sure it is RIC XI, 21a or 21b or 21c for Cyzicus.

It is a type of brockage in which two blanks were placed one atop the other in the anvil die and stuck at the same time. This is the coin that was on top and received the impression from the hammer die for the reverse but was impacted by the unstruck portion of the other blank for its obverse. The upper blank apparently slid to one side on impact which would account for the severe off center strike. (Of course the celator may have seen the problem on the approach and tried to jerk the hammer die off course resulting in an off center stike - who knows?)

That is how I read it.