A diamond single-stone ring, by Bulgari

A diamond single-stone ring, by Bulgari. Photo Bonhams

The marquise-cut diamond, weighing 8.37 carats, to baguette-cut diamond shoulders,signed Bulgari, ring size 6, maker's case. Sold for HKD4,912,000

Accompanied by a GIA certificate stating that the diamond is E colour, internally flawless. Certificate number 5131215488, dated 23rd March 2011.

Also accompanied by a GIA certificate stating that the diamond is type IIa. Certificate number 5131215488, dated 22nd March 2011.

Bonhams. Fine Jewellery & Jadeite, Hong Kong, Island Shangri-La Hotel, 26 May 2011 at 14:00 www.bonhams.com