Constantine I, AE follis, Siscia. 320 AD.

CONST-ANTINVS AVG, helmeted, cuirassed bust right.
VIRTVS-EXERCIT, Standard inscribed VOT / XX in two lines 
standing on ground, captive seated on either side
Chi-rho in left field.
Mintmark: ASIS

Not in RIC. Rev. Num. 1866 p.85; Bikic-Do hoard 752 var (mintmark), very rare.

Contributed by "clueless" of the Forum Ancient Coins, Dez, 2011