An impressive diamond ring.Photo: Christie's Images Ltd. 2011

Set with an oval-cut diamond, weighing approximately 46.51 carats, flanked on either side by a pear-shaped diamond, weighing approximately 1.00 and 1.01 carats, mounted in platinum. Estimate $2,500,000 - $3,500,000 - Price Realized $4,226,500

With report 5131361767 dated 22 April 2011 from the Gemological Institute of America stating that the oval-cut diamond is E color, VVS2 clarity

With reports 12344176 and 12038592 dated 3 January 2003 and 28 May 2002 from the Gemological Institute of America stating that the pear-shaped diamonds, weighing approximately 1.00 and 1.01 carats, are D color, VS1 and VS2 clarity respectively

An important diamond ring. Photo: Christie's Images Ltd. 2011

Set with a pear-shaped diamond, weighing approximately 10.01 carats, flanked on either side by a pear-shaped diamond, each weighing approximately 1.02 carats, mounted in platinum. Estimate $1,100,000 - $1,500,000 -  Price Realized $1,314,500 

With report 2125860521 dated 9 February 2011 from the Gemological Institute of America stating that the pear-shaped diamond is D color, internally flawless clarity

With reports 5103947167 and 16926784 dated 15 March 2010 and 1 May 2008 from the Gemological Institute of America stating that the two pear-shaped diamonds, each weighing approximately 1.02 carats, are D color, internally flawless clarity (3)

A diamond ring, by Sabbadini. Photo: Christie's Images Ltd. 2011

Set with a rectangular-cut diamond, weighing approximately 9.76 carats, the shoulders set with modified hexagonal-cut diamonds, mounted in platinum. Signed Sabbadini. Estimate $200,000 - $300,000 -  Price Realized $434,500

With report 2135336357 dated 20 April 2011 from the Gemological Institute of America stating that the diamond is H color, VVS1 clarity; accompanied by a working diagram indicating that the clarity may be potentially internally flawless

A diamond ring. Photo: Christie's Images Ltd. 2011

Set with a square emerald-cut diamond, weighing approximately 10.42 carats, the shoulders set with circular-cut diamonds, mounted in platinum. Estimate $300,000 - $500,000- Price Realized $422,500

With report 1132131201 dated 28 February 2011 from the Gemological Institute of America stating that the diamond is G color, VS2 clarity

A diamond ring. Photo: Christie's Images Ltd. 2011

Set with a marquise-cut diamond, weighing approximately 5.30 carats, the sculpted platinum band set with a marquise-cut diamond terminal, weighing approximately 0.33 carat, mounted in platinum. Estimate $250,000 - $350,000- Price Realized $362,500

With report 17492414 dated 18 December 2008 from the Gemological Institute of America stating that the marquise-cut diamond, weighing approximately 5.30 carats, is D color, internally flawless clarity

With report 17201789 dated 22 May 2008 from the Gemological Institute of America stating that the marquise-cut diamond, weighing 0.33 carat, is D color, internally flawless clarity

Each suspending a pear-shaped diamond, weighing approximately 3.51 and 3.40 carats, from a pear-shaped diamond link, weighing approximately 0.70 and 0.68 carats, to the pear-shaped diamond surmount, each weighing approximately 1.01 carats, mounted in platinum. Estimate $250,000 - $300,000- Price Realized $362,500

With six reports dated from 29 October 2010 to 18 August 2005 from the Gemological Institute of America stating that the six pear-shaped diamonds, weighing from approximately 3.51 to 0.68 carats, are D color, internally flawless clarity (6)

A diamond rivière necklace. Photo: Christie's Images Ltd. 2011

Of sixty-seven graduated circular-cut diamonds, mounted in platinum, 15¼ ins. Estimate $250,000 - $350,000 - Price Realized $314,500

With sixteen reports dated from 4 February 2010 to 8 March 2006 from the Gemological Institute of America stating that sixteen of the diamonds, weighing from approximately 3.00 to 0.73 carats, range from D to F color, and from internally flawless to SI1 clarity

Christies's. Important Jewels, 14 June 2011, New York, Rockefeller Plaza www.christies.com