Sotheby's auction of November 10

Sotheby's will hold a series of auctions from the diamond collection of the late Rachel Lambert Mellon - an American horticulturalist, gardener, philanthropist, art and diamond jewelry collector. The jewelry and loose diamonds sale will begin on November 10 with a curated selection of fine art that spans four centuries. Mellon's diamond jewelry will be auctioned on the evening of November 20, followed by a three-day sale of various fine jewelry pieces from Mellon's residences. The auctions are estimated to achieve in excess of $100 million. A 9.75 carat pear shaped fancy vivid blue diamond with internally flawless diamond clarity is priced to sell for between $10 million and $15 million.

A 9.15 carat, VS1 diamond clarity, natural fancy color blue diamond pendant, mounted in platinum, is offered with a presale estimate of $1 million to $1.5 million. Of the top jewelry lots, Sotheby's will offer a gold and diamond necklace featuring a graduated jewelry design, set with 29 old European cut diamonds and weighing approximately 111 carats. By Cartier, circa 1900, it's set with a round, fancy deep yellow diamond of 4.2 carats, this piece is estimated to sell for between $1.25 million to $1.5 million.