A diamond tiara, circa 1840. Photo Bonhams.

Designed as an articulated wreath of highly stylised blooms amongst meandering foliate motifs, set throughout with cushion-shaped, pear-shaped and old brilliant-cut diamonds, mounted in silver and gold, diamonds approximately 50.00 carats total, seven smaller diamonds deficient, detachable from frame and may be worn as a necklace, centrepiece may be detached and worn as a brooch. Estimate £20,000 - 30,000 (€24,000 - 36,000)

Bonhams.FINE JEWELLERY, London, New Bond Street, 30 Apr 2014 - www.bonhams.com