An 11.80 carats coloured diamond single-stone ring. Estimate £80,000 - 120,000 (€110,000 - 160,000). Photo: Bonhams.

The old brilliant-cut diamond, weighing 11.80 carats, within a single-cut diamond surround and similarly-cut diamond shoulders, ring size L (sizing band)

Accompanied by a report from GCS stating that the diamond is Light Yellow, natural colour, VVS2 clarity. Report number 5775-1983, dated 12 May 2015.

Bonham's. FINE JEWELLERY, 24 Sep 2015 12:00 BST - LONDON, NEW BOND STREET