A Giuliano multi-gem set brooch

A Giuliano multi-gem set brooch, the central round old-cut diamond, flanked by a round faceted ruby to one side and a round faceted sapphire to the other, all gems set within a decorative scrolled openwork blue and white enamel frame, overall measurements approximately 37 x 15 mm, circa 1860, gross weight 5.6 grams, slight restoration to enamel.