The Galaxy winner Sweet Idea has fetched $1.6 million as the highlight lot of the Magic Millions National Broodmare Sale.

A $240,000 yearling purchase, Sweet Idea banked more than $2.4 million in racetrack earnings under the guidance of trainer Gai Waterhouse.

She went through the sale ring on Wednesday as the winner of eight races from 19 starts with her eight placings including a narrow defeat in last year's Group One Coolmore Classic.

A daughter of leading sire Snitzel, Sweet Idea was also Group One placed in the Myer Classic, Memsie Stakes and the Golden Slipper.

The four-year-old came from midfield to score a first-up win in the Group One Galaxy at her only autumn appearance before going amiss.

Nick Vass, a part-owner of Sweet Idea, was the successful bidder.

Villa Verde was another high-profile racemare to go under the hammer, fetching $1.1 million while last year's Queensland Oaks runner-up Arabian Gold went for $800,000.