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This ruby and diamond flower brooch, originally from Van Cleef & Arpels, Paris, in 1967, contains round and baguette diamonds weighing approximately 4.05 carats. The petals are "mystery-set" with calibre-cut rubies, mounted in platinum and 18 karat gold. Van Cleef & Arpels created the mystery setting technique, in which prongs are concealed beneath the gems they hold.
Estimated value: $60,000 to 80,000
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This pieces is from the collection of Virginia winemaker and philanthropist Patrcia Kluge, including this platinum, sapphire and diamond ring. The cushion-shaped sapphire, weighing about 21.30 carats, is framed by round and single-cut diamonds weighing about 5.7 carats.
Estimated value: $200,000 to $300,000
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Birds of a feather
Crafted around 1940, this brooch depicts birds in flight. The wings are set with segments of cabochon moonstones, accented by round and single-cut diamonds and calibré-cut rubies.
Estimated value: $25,000 to $35,000
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Sotheby is believes this to be the first necklace set entirely with fancy-vivid yellow diamonds ever to appear at auction. The 42 diamonds weigh a total of 100.17 carats.
Estimated value: $2 million to $3 million
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Pear-shaped pair
These pendant earrings feature pear-shaped emeralds weighing 10.58 and 9.76 carats, and diamonds weighing approximately 2.50 carats, mounted in platinum.
Estimated value: $350,000 to $450,000
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Dating to about 1890, this brooch/hair ornament is in the shape of a flying swallow. It has diamonds applied with white enamel, mounted in 10 karat gold.
Estimated value: $30,000 to $40,000
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Dietrich's diamonds
Dating to about 1930, this platinum and diamond brooch once belonged to actress Marlene Dietrich.
Estimated value: $30,000 to $50,000