RAPAPORT... A 76.46-carat diamond necklace is expected to fetch up to $6 million at the upcoming Christie's New York Magnificent Jewels sale.The piece features a heart brilliant-cut, D-color, VVS2-clarity, type IIa diamond center stone, accompanied by 46 stones of the same shape ranging from 0.46 to 3.03 carats. It will be one of the top items at the June 8 jewelry auction, Christie's said last week.Also on offer will be a bracelet by designer Carvin French containing diamonds of different shapes and colors, all of them either in the fancy-pink or the fancy-red ranges. Meanwhile, a cut-cornered square modified brilliant-cut, 58.49-carat, fancy-vivid-yellow diamond ring is set to go under the hammer. Both jewels are estimated at $1.5 million to $2.5 million.Other notable items include a pear brilliant-cut, 20.23-carat, D-flawless diamond with a presale valuation of up to $2 million. A pair of earrings estimated at up to $1.8 million will also be seeking a buyer. The set contains pear-shaped emeralds weighing 13.79 and 12.14 carats, suspended from old European-cut diamonds ranging from 1.28 to 5.55 carats.The sale will include 12 jewels by designer JAR from the estate of American philanthropist, publisher and socialite Ann Getty. The group is one of the largest private collections of jewelry by the designer to appear at auction, Christie's noted.Those items will join the Light of Africa diamond, which will headline the auction. The emerald-cut, 103.49-carat, D-flawless, type IIa stone could sell for up to $18 million.Image: The 76.46-carat, heart-shaped diamond ring. (Christie's)