A chrysoberyl devant de corsage brooch

A chrysoberyl devant de corsage brooch, possibly Portugal, 18th century, the top designed as a ribbon bow issuing foliate sprays, suspending a pear-shaped drop, set with oval, cushion- and pear-shaped chrysoberyls, mounted in silver, measuring approximately 7.8cm x 6.7cm, upper central section and two side pendants deficient, later brooch fittings