Carausius, AR denarius, London. AD 286-293. 3.76 g. 

IMP CARAVSIVS PF AVG, laureate, draped and cuirassed bust right.
VOTVM PVBLIC, Altar inscribed MVL-TIS XX-IMP in three lines.
Mintmark RSR. 

RIC V-2, London 595; Webb 655; RSC 116; Shiel 94-96.
Rated R3.

With permission of Spink auction 8006, March 2008.
Estimate £600-£700.