Bronze as, 25mm, 11.75gm, issued AD 154/155. Rome mint.
Obv: ANTONINVS AVG PIVS PP TRP XVIII, Laureate head facing right.
Rev: BRITA[NNIA COS] IIII (SC in ex.), Britannia seated to left on rock, to left shield and sceptre.
References: Sear 4296, RIC 934.
Dark toning, rare.
The Antonine Wall was built to enclose areas beyond Hadrian's Wall that were captured in Antoninus' reign. Around 155 the Brigantes, a British tribe in the North, revolted.