Justinian I. AE Follis 27mm, 16.75 g, Constantinople mint, AD 527-565. 

DN IVSTINIANVS PF AVG, pearl-diademed, draped and cuirassed 
bust right; crescent over chi-rho in right field.
Large M; solid six-pointed star to left, cross above, 
crescent turned outwards to right, Epsilon below.
Mintmark CON.

SB 162 var (symbols in right field and star type on rev); 
DOC 32 var. (ditto); MIBE 88 var (ditto) SB 162 var. (same).

with permission of Jean Elsen & ses Fils S.A. auction 116, Lot 621, March 2013.