“The World of Heidi Horten”; 3–15 May, Geneva and Online

Billed as the largest and most valuable private jewellery collection to be auctioned, the jewellery of billionaire Austrian art collector Heidi Horten will go under the hammer at Christie’s this month in Geneva, with the proceeds benefiting the Heidi Horten Foundation. With a pre-sale estimate of more than US$150 million, the collection comprises highlights such as Bulgari creations spanning the ’70s to the present day, a double-strand jadeite necklace with a Cartier diamond clasp, and more.

• READ MORE: On Exploring Jewelled Watches With Bulgari’s Antoine Pin

“The Art of F. P. Journe”; 12 May, Geneva

Forty timepieces by F.P. Journe will be offered this month in Geneva at a singular auction celebrating a single independent watchmaker. Christie’s “The Art of F.P. Journe” comprises key creations by the watchmaking manufacture such as the Tourbillon Souverain with a jade dial, the Centigraphe Souverain chronograph with a red chrome dial, the Octa Calendrier with a black mother-of-pearl dial made for Sincere Fine Watches, and an early example of the Pré-Souscription platinum Chronomètre à Résonance.

“The Imperial Patek Philippe Sale”; 23 May, Hong Kong

In association with Bacs & Russo, Phillips announces its auction of the Patek Philippe Reference 96 Quantieme Lune that belonged to the last emperor of the Qing Dynasty, Aisin-Giro Puyi. Only the eighth known example of the Patek Philippe Reference 96 of such complication, this timepiece features a triple date and moonphase, a Victorin Piguet ébauche movement produced in 1929, within a platinum Calatrava case by Antoine Gerlach.

• READ MORE: A Patek Philippe Watch Owned by China’s Last Emperor is Up for Auction

“The Ultimate Collection” And “Important Watches”; 26 May, Hong Kong

Later this month, Christie’s Hong Kong will host two live auctions, “The Ultimate Collection” for contemporary and vintage tickers, and “Important Watches” for extremely limited and valuable timepieces. The former includes the rare Patek Philippe Reference 3448 self-winding perpetual calendar from 1962, while the latter is headlined by the Patek Philippe Reference 2523J Dual Crown World Time with a map of North America on the cloisonné enamel dial, with a low pre-sale estimate of HK$55 million.

This article first appeared on Grazia Singapore.

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