Magnentius AE3, Arles. 

DN MAGNEN-TIVS PF AVG, bare-headed, draped, cuirassed bust right, A behind head.
GLORIA ROMANORVM, emperor in military dress galloping right, 
no shield, wielding spear at a barbarian kneeling left 
before the horse.
L in left field, star in upper right field.
Mintmark SAR.

Not in RIC. RIC 155 var (mintmark)
With permission of Paul-Francis Jacquier, Auction 38, Lot 629, Sept. 2013.
Estimate: 200 Euro.