A single-owner collection of unique Patek Philippe clocks will provide the main draw of Sotheby's Magnificent Clocks auction, which will be held on April 7 in Hong Kong.

This unique piece was made in 1990 and features 18k gold, silver, mother of pearl, diamonds, rubies and emeralds

The series of 13 spectacular clocks were all made especially for one important private collector. A piece entitled Pearl from the Golden Oyster Clock will lead bids, estimated at $450,000-710,000.

Also starring from the collection are two of Cartier's famed mystery clocks, with Flamingo and Lotus Automaton Clock expected to see bids of up to $320,000.

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