A rare Rolex ‘Rainbow’ Daytona is expected to be the highlight of an upcoming watch auction in Sydney, where a collection of 28 luxury Swiss timepieces is forecast to achieve more than $2 million in total sales.

The auction, organised by First State Auctions and scheduled for 19 July, includes sought-after watches from prestigious manufacturers such as Audemars Piguet, Richard Mille and Rolex.The standout lot is the Rolex Rainbow Daytona, an 18-carat gold chronograph distinguished by its multicoloured gemstone-set bezel.

Auctioneers estimate the watch alone could sell for more than $500,000, which would make it the most expensive watch ever sold at auction in Australia if it reaches expectations.

The collection is reportedly being offered by a mystery vendor described only as a prominent Australian technology founder, although no further details about the owner's identity have been disclosed.

The sale reflects the continued strength of the high-end collector watch market, where rare and limited-production models from leading Swiss brands continue to attract significant interest from enthusiasts and investors.

With several highly desirable pieces included in the catalogue, the auction house is optimistic that the event will establish new benchmarks for the Australian luxury watch market, while the Rainbow Daytona is expected to attract the greatest attention from bidders due to its rarity, distinctive design and strong international demand.