Marcus Aurelius A.D.161-180  AE Sestertius,  33mm 26.94g minted in A.D.170. 
Rare coin type, depicting departure of the Emperor to military campain against Marcomanni and Quadi tribes on the Danubian border.
Obv. Bare head  right.
M.ANTONINVS AVG TR.P. XXIIII
Rev. Marcus Aurelius on horse right, wearing cuirass, holding spear; in front soldier with spear and shield, three soldiers holding standards behind.
PROFECTIO AVG  S.C. in exergue 
Refferece : R.I.C.977, Cohen 503

Coin is guaranteed to be authentic.