A pink topaz necklace, 1830s, the front composed of articulated laurel leaf links

A pink topaz necklace, 1830s, the front composed of articulated laurel leaf links, to a central motif suspending a detachable pendant/brooch, constructed from gold cannetille and set with pear-shaped, circular-cut, oval and cushion-shaped pink topazes in foil-backed settings, the back composed of two belcher link and one rope twist chains in stamped gold linking, to a similar pink topaz cluster clasp, necklace length 42cm, length at front including pendant 8.2cm, pendant with later brooch fittings, case stamped H. Knowles Brown Ltd