Roman enamelled copper-alloy disc brooch

Roman bronze disc-brooch, diam. 2.7cm. In centre a shallow cast cell with lost setting; around this a plain ridge, then a zone of bronze dots in relief possibly in the remains of an enamel field; then a border of scallop decoration. The whole very decayed. On the back a damaged pin catch, and at the other side a pair of pierced lugs with a bronze bolt between and the remainder of the spring coil, also bronze.