An antique diamond ring, circa 1900, set with a heart-shaped diamond, weighing 5.05 carats, with old European-cut diamond shoulders and plain mount;mounted in eighteen karat gold and platinum; size 5.  Estimate US$ 50,000 - 70,000//€38,000 - 53,000. Photo: Courtesy of Bonhams.

NEW YORK – An unusual heart-shaped antique diamond ring (est. $50,000-70,000) will be one of many highlights in Bonhams June 19 Fine Jewellery auction in New York. The ring, made circa 1900, is centred by a 5.05 carat diamond mounted in eighteen karat yellow gold and platinum. Cut in the old-mine style, this antique treasure was designed for maximum sparkle in candlelight, giving it a soft, romantic glow.

"Old-mine heart shaped diamonds are rare and infrequent in today's market. This particular stone exudes the charm and warmth typically found in old-mine cut stones and offers a late Victorian sentiment with a dash of romance. It is an ideal engagement ring for a collector who admires antique jewels," remarks Susan Abeles, Bonhams Director of Jewellery in the US. "I am sure bidders will experience love at first sight."

The antique ring isn't the only heart-stealer up for auction: Bonhams will also offer coloured heart-shaped diamonds, including a diamond necklace featuring a heart-shaped fancy light yellow diamond pendant, weighing 7.09 carats, framed by pavé-set diamonds and suspended from a heart-shaped diamond link chain (est. $60,000 - 80,000).

An emerald and diamond necklace, Harry Winston, designed as cut-cornered rectangular-cut emerald, weighing 13.45 carats, within a pear and marquise-cut diamond cluster surround, completed by a similarly designed necklace; necklace signed Winston, pendant signed HW for Harry Winston; with signed box; estimated total diamond weight: 32.00 carats; mounted in platinum and eighteen karat white gold; length: 16in. Estimate: US $ 180,000 - 280,000/€130,000 - 210,000. Photo: Courtesy of Bonhams

Every jewellery lover's heart is sure to be warmed by the romantic and feminine designs on offer, like the classic emerald and diamond necklace from Harry Winston (est. $175,000-275,000). This sixteen inch sparkler features a 13 carat rectangular-cut emerald pendant on a marquise and pear-cut diamond necklace in platinum and white gold, with a total diamond weight of approximately 32 carats. An elegant seventeen inch diamond rivière necklace mounted in platinum and comprised of ninety-five round brilliant-cut diamonds for an estimated total diamond weight of 33.90 carats (est. $75,000-95,000) is sure to catch bidder's eyes.

A diamond rivière necklace comprising ninety-five round brilliant-cut diamonds; largest diamond weighing approximately: 1.50 carats; estimated total diamond weight: 33.90 carats; mounted in platinum; length: 17 1/2in. Estimate: US$ 75,000 - 95,000:€57,000 - 72,000. Photo: Courtesy of Bonhams

An art deco diamond and sapphire bracelet, Oscar Heyman & Brothers, circa 1923 of geometric design, set throughout with transitional and square step cut-diamonds, with French-cut sapphire detail; centering three triangular-cut diamonds, weighing 2.87 carats total; with maker's mark for Oscar Heyman & Brothers; no. 10517; estimated remaining total diamond weight: 24.60 carats; mounted in platinum; length: 7 1/8in. Estimate: US$ 30,000 - 60,000/€23,000 - 45,000. Photo: Courtesy of Bonhams

On-trend art deco designs will also be up for auction, including a geometric 1923 diamond and sapphire bracelet by Oscar Heyman & Brothers (est. $30,000-60,000). Featuring French cut sapphires and total diamond weight of nearly 28 carats, the fine detail of this early art deco example is exceptional. A white jadeite jade, ruby and diamond match safe, from Cartier, circa 1920, would have made the ultimate flapper accessory (est. $5,000-7,000), especially when paired with a late art deco sapphire and diamond double clip brooch from Raymond Yard (est. $20,000-30,000).

A white jadeite jade, ruby and diamond match safe, Cartier, circa 1920. Of rectangular outline, enhanced by rose-cut thumb piece and hinges, accented by calibré and cabochon-cut rubies, the front enhanced by a round brilliant-cut ruby and rose-cut diamond foliate motif; signed Cartier Paris, Londres, New York; with maker's mark for Henri Lavabre; mounted in platinum; measuring: 1 1/16 x 1 1/4in. Estimate: US$ 5,000 - 7,000/€3,800 - 5,300. Photo: Courtesy of Bonhams

A late art deco sapphire and diamond double clip brooch, Raymond Yard, circa 1935. Each of openwork geometric design, the transitional-cut diamond shield-shaped plaques decorated with variously-cut sapphires, enhanced by baguette, square and kite-shaped diamonds; signed Yard for Raymond Yard, with signed box; estimated total diamond weight: 6.55 carats; mounted in platinum; length: 2 1/4in. Estimate: US$ 20,000 - 30,000/€15,000 - 23,000. Photo: Courtesy of Bonhams

"One of a kind pieces of art deco jewellery are definitely in the spotlight right now," explained Virginia Salem, the Director of the Jewellery Department at Bonhams New York. "The innovative style and exquisite craftsmanship of the 1920s and early 1930s make period art deco jewellery a must-have for any serious collector."

Additional highlights include an emerald-cut diamond, weighing 12.13 carats (est. $200,000-300,000); a fancy coloured diamond and diamond ring set with a radiant-cut fancy deep yellow diamond, weighing 16.03 carats, flanked by fancy-cut diamonds (est. $180,000-250,000); and a star sapphire and diamond ring from Ann Garrett centering a round cabochon star sapphire, weighing 42.87 carats (est. $125,000-175,000).

A diamond ring centering a cut-corned rectangular modified brilliant-cut diamond, weighing 12.13 carats, with triangular-shaped diamond shoulders in a plain mount; estimated remaining total diamond weight: 3.00 carats; mounted in platinum; size 8. Estimate US$ 200,000 - 300,000/€150,000 - 230,000. Photo: Courtesy of Bonhams

A fancy colored diamond and diamond ring, set with a cut-cornered square modified brilliant-cut fancy deep yellow diamond, weighing 16.03 carats, flanked by fancy-cut diamonds; estimated remaining total diamond weight: 2.00 carats; mounted in eighteen karat gold; size 5 (with sizer). Estimate: US$ 180,000 - 250,000/€140,000 - 190,000. Photo: Courtesy of Bonhams

A star sapphire and diamond ring, Ann Garrett, centering a round cabochon star sapphire, weighing 42.87 carats, within a polished gold surround, accented by round brilliant-cut diamond swirl motifs, completed by a squared shank; signed Garrett for Ann Garrett; estimated total diamond weight: 2.00 carats; mounted in eighteen karat gold; size 6 3/4. Estimate: US$ 130,000 - 180,000/€94,000 - 130,000. Photo: Courtesy of Bonhams

Bonhams Fine Jewellery sale will take place on June 19 in New York. The sale will preview at Bonhams San Francisco May 31-June 2, at Bonhams Los Angeles June 7-9, and at Bonhams New York from June 15-19.