A Cartier diamond and emerald necklace valued at $7m-10m will highlight Christie's November 12 jewellery auction in Geneva.
The necklace was designed in London in 1937 and features the Andean Cross - an emerald that once belonged to Queen Isabel II of Spain and Empress Eugenie of France.
The necklace comes from the collection of Simon Patino (1860-1947), the Bolivian mining tycoon dubbed the "Andean Rockefeller" and one of the five richest men in the world during the 1930s.
A 32.65 carat Chaumet diamond ring will also feature, with a $2.3m-2.8m estimate.
Francois Curiel, international head of Christie's jewellery department, commented: "When one looks back to the great jewellery collections of the 20th Century, the name of Patino always comes up. In the 1930s and 1940s, during one of the greatest periods of jewellery design, fabulous gemstones and jewels were purchased by Simon Patino and kept in family hands over several generations.
"The Cartier emerald and diamond parure and the 32ct diamond ring by Chaumet are stunning examples from the 'Patino casket', which illustrate perfectly the high standards and great eye of this visionary man.
"History, provenance and outstanding quality are here combined with the signatures of two of the oldest and greatest jewellery houses. These are true treasures for the world's collectors of today."
Jewellery from the estate of Helene Rochas (1927-2011), wife of Marcel Rochas, a French fashion designer, will also feature. A shoulder brooch by Rene Boivin in the shape of a tiger will carry a $202,969-286,890 estimate.
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