A rare Chelsea Derby drum shaped box and hinged cover, with gilt metal mounts, the cover moulded

A rare Chelsea Derby drum shaped box and hinged cover, with gilt metal mounts, the cover moulded with a flowerhead medallion, and an interlinked band, picked out in blue, puce and gilt, the base with European flowers and leaves, in coloured enamels, the interior of the cover finely painted with a basket of flowers, on a stone ledge, 7. 6cm diameter (3"), circa 1785 (cover cracked)