Carausius, AE antoninianus, uncertain British mint. 

IMP CARAVSIVS P AVG, radiate, draped and cuirassed bust right.
VOTA QVI CAE, Emperor standing right, receiving Victory from Roma, seated left on shield and holding spear.

Mintmark MX. 

RIC V-2, 1095, Little Orme hoard (1907); IARCW 921/105.
Rated R3.