Masterpieces belonging to controversial former Sotheby's owner A. Alfred Taubman went on show in Hong Kong Friday, touted as the most valuable private collection ever offered at auction.

Sotheby's estimates the 500 works will fetch US$500 million -- they include Modigliani's "Portrait de Paulette Jourdain", as well as pieces by Picasso, Degas, Willem de Kooning and Mark Rothko.

"It was collected over 70 years with the great eye of Alfred Taubman... we have Old Masters, impressionists, modern pictures as well as contemporary works on display," Sotheby's Asia chairman Patti Wong told AFP.  

Sotheby's beat Christie's to the Taubman collection -- both had vied to auction it.

But Christie's unveiled its own Modigliani in Hong Kong Friday, which is also set to break records.

Christie's says that the reclining nude "Nu Couché" by the modern Italian painter will be the most valuable work by the artist ever offered at auction -- predicted to fetch at least US100 million.

The Taubman collection will go on sale in four separate Sotheby's auctions in New York from November to January.

Christie's Modigliani will also go on sale in November in New York.

Taubman, who died in April aged 91, was an entrepreneur and retail magnate, bringing shopping malls to suburban areas of the United States.

After buying Sotheby's in 1983 he took it public, opening it up to a new market of wealthy collectors.

But he became mired in controversy over a price-fixing scandal between Sotheby's and Christie's for which he was jailed in 2002, despite maintaining his innocence.

Taubman sold his controlling interest in Sotheby's in 2005.

"My brother, sister and I all felt it would be too difficult to start picking pieces out, and felt the fairest solution was to sell everything," Taubman's son William told AFP.

"I would hope that collectors who share my father's taste will be interested, and of course there are certain pieces that may end up in institutions."

Taubman's collection is touring before the New York auction, with its first stop in Hong Kong -- Asia's art hub.

It comes as fears grow that China's economic slowdown and its knock-on effects could dent the region's burgeoning appetite for the art market.

But Sotheby's Wong said collectors in Asia were still on the lookout for great pieces.

"There is financial market turmoil in China right now, but we're talking about a much deeper pool of collectors," says Wong.

"The wealth has not been accumulated or made necessarily in the financial markets, so people are still quite optimistic."
Source: AFP