Kay Saatchi, ex-wife of leading British art patron Charles, is selling off part of her own collection at a Christie's
auction in June and expects to raise up to 3.4 million pounds ($5.4 million).
The highlight of the sale, which will form part of the post-war and contemporary art evening auction in London on June 28, is a larger-than-life yet disturbingly realistic model of a seated and naked baby by Ron Mueck.
"Big Baby," which measures nearly three feet high and is the Australian artist's first documented work, dates from 1996 and is estimated to be worth 800,000-1.2 million pounds.
A series of five drawings by veteran British painter Lucian Freud dating from the 1940s is expected to fetch between 770,000 and 1.2 million pounds combined.
Christie's said it was the most important group of works on paper by the artist ever to come to auction.
The third main lot is a painting by Paula Rego, "Looking Back," valued at 600-800,000 pounds.
Another 24 less important works will be offered in a day sale on June 29.
"After 25 years in London, I have decided to move my base to Los Angeles and to offer a selection of works from my art collection," Kay Saatchi said in a statement.
She said the sale was "partly for practical reasons and partly for the excitement and challenge of building a new collection in a new environment.
"Inevitably there is sadness in leaving a city I love and in parting with works of art I treasure. But my hope is that the move to Los Angeles will be not so much a departure as a new beginning," she added.
Kay Saatchi married art collector Charles in 1990 and they divorced in 2001. Dealers believe she deserves some credit in her husband's huge success and influence in buying, selling and promoting art.
Charles Saatchi famously championed the new generation of "YBAs" (Young British Artists) which included Damien Hirst and Tracey Emin and burst on to the contemporary art scene with its ability to shock and sharply divide public opinion.
(Reporting by Mike Collett-White; Editing by Steve Addison)