Magnentius, AV solidus, Rome mint. AD 351. 

IMP CAE MAGNENTIVS AVG, bare-headed, draped, cuirassed bust right.
VICTORIA AVG LIB ROMANOR, Victory standing right, holding 
branch, facing Libertas, standing left, holding sceptre,
holding a trophy between them. 

Mintmark RB
RIC VIII Rome 163 var (officina letter); Sear 18740.
Very rare.

Contributed by Arie van Herwijnen, Nov. 2015.