Another lot at Sotheby's spring sale in Geneva in 2014 was this natural pearl necklace with rubies and diamonds, which went under the hammer for $1.02 million, achieving more than four times its high estimate.

Another lot at Sotheby's spring sale in Geneva in 2014 was this natural pearl necklace with rubies and diamonds, which went under the hammer for $1.02 million, achieving more than four times its high estimate.

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