19.51-Carat Harry Winston Diamond Ring May Fetch $1.8 Million

A Harry Winston platinum ring centered with an emerald-cut 19.51-carat diamond will be one of the top items being offered at Sotheby’s New York Important Jewels auction on September 24.

The ring, flanked by two triangle-shaped diamonds weighing 2.92 carats, has a pre-auction estimate of $1.2 - $1.8 million. It is from the family of George Rothman, the successful real estate developer and philanthropist who created the Rothman Foundation. It is the top lot among a collection of jewelry the family has put on sale that include pieces by Bulgari, David Webb and Van Cleef & Arpels.

The Harry Winston ring is one of three such rings that have high estimates of more than $1 million at the upcoming sale. The others are:

* A pear-shaped diamond weighing 15.10 carats, flanked by two smaller pear-shaped diamonds weighing approximately 2 carats will also appear in the sale with an estimate of $1.25 million - $1.75 million. The ownership is identified by the auction house as being from a New York estate.

* A 9.77-carat, cut-cornered rectangular step-cut diamond accented by small round diamonds weighing approximately 0.70 carat, and mounted on platinum. The ring, which is identified as the property of a lady from Texas, has an estimate of $800,000 to $1.2 million. 

Fancy colored diamonds have made their mark in recent years on the auction market and Sotheby’s leader in this category for the upcoming auction is a 1.08-carat pear-shaped fancy vivid blue diamond (pictured above), on a platinum mounting accented by round near colorless diamonds. This item has an estimate of $450,000 - $650,000.

The upcoming auction will also feature several pieces from the collection of Alex & Elisabeth Lewyt, featuring custom-designed and period pieces by French jewelers such as Schlumberger, Suzanne Belperron and René Boivin. Items of note from the Lewyt collection include:

* A platinum, palladium and diamond triple-band cuff-bracelet by Belperron (pictured above). It was worn by Elisabeth Lewyt on her wedding day. The bracelet has three tapered rows set with 75 old mine-cut diamonds weighing approximately 16.95 carats. It has an estimate of $40,000 to $60,000. 

* An 18k yellow gold reclining Labrador retriever brooch by René Boivin (pictured above). The torso, ears, paws and tail of the dog are set with numerous round and single-cut diamonds of near colorless, brown and yellow hues weighing approximately 28.95 carats. The collar is set with 19 buff-topped rubies. The eyes are made of two cabochon citrines and the nose and pads on the back paws are accented by a blackened gold. Its estimate is $70,000 - $90,000.

* A platinum and diamond double-clip pendant-brooch by Schlumberger, set with marquise-shaped diamonds weighing 5.22 and 5.28 carats, both E color, VS1 clarity; estimate $200,00 - $300,000.

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