A 19th century emerald, ruby and diamond bow brooch, Hungarian. Photo Bonhams

The tied ribbon bow set throughout with vari-cut diamonds, rubies and emeralds, some in foiled closed-back settings, with a central inverted square-cut emerald, mounted in silver and gold, detachable brooch fitting, length 5.2cm. Estimate: £2,500 - 3,000, US$ 4,100 - 4,900

Bonhams. Fine Jewellery, 21 Sep 2011, New Bond Street www.bonhams.com