SEVERINA, Antoninianus Rome mint. Struck 275 AD. 

SEVERINA AVG, diademed bust right on crescent.
CONCORDIAE MILITVM, Concordia standing left, holding two standards. 

R-Digamma across fields, mintmark XXI
RIC V-1, 4; Cohen 7. 

Sold by Noble Numismatics Pty Ltd - Auction 91, Lot 3739, June 2009.