A 19th century ruby and diamond necklace, designed as an articulated series of old brilliant-cut diamonds in pinched-collet settings, leading to a scrolled foliate frontispiece similarly-set throughout and suspending a pear-shaped pendant drop, formed as an outer diamond frame with an oval-cut ruby and diamond cluster within, mounted in silver and gold, numbered ‘9571’ with French eagle’s head assay marks, composite, total diamond weight approximately 9.80 carats, length 37cm. £4,000-£6,000