The annual Frieze Art Fair will go ahead as usual in a giant marquee in Regent's Park, a grid of 175 galleries teeming with potential buyers and thousands of contemporary art lovers keen to keep up with the latest trends in a fast-moving world.

And there are the spin-off events across the capital designed to lure the world's wealthiest buyers - auctions, rival fairs, parties, gallery openings, exhibitions and discreet viewings far from the hullabaloo.

But unlike previous editions, the October 11-14 fair this year comes with a separate Frieze Masters event featuring 96 galleries offering works from across the last 4,000 years.

The reasons for the shift are both commercial and cultural.

Organisers and exhibiting galleries are hoping for more crossover business between contemporary art collectors and those more interested in older works.

They also want to explore art's relationship with the past, representing an acceptance that what came before should be appreciated as well as challenged by iconoclastic young artists.

"I suppose what makes it interesting is what's come out of conversations with contemporary artists," said Victoria Siddall, director of the new fair. "It becomes apparent that a lot of them are looking at works that were made a long time ago.

"All galleries are interested in meeting new clients," she told Reuters. "There are old master and contemporary galleries, and I hope there will be a crossover. It would be great to broaden people's horizons in terms of what they collect."

"MEDICI" BUYERS

That crossover is already happening.

Among the most coveted clients for auction houses and galleries are so-called "Medici"-style buyers who acquire art across different periods and genres.

Sotheby's said 30 percent of buyers at its old master drawing sales had also bought art at its contemporary auctions, compared with seven percent in 2007.

It is no coincidence that it is displaying Raphael's 1519 "Head of an Apostle", which is worth up to $24 million, alongside Jackson Pollock, Francis Bacon and Gerhard Richter at its London headquarters this week.

Artists are also embracing Frieze's shift to the past.

The fair has organised a series of conversations bringing together leading contemporary artists with major curators.

On Thursday, London-born contemporary painter Cecily Brown talks with National Gallery director Nicholas Penny who is more used to talking about Raphael than Richter.

For Matthew Slotover, who with Amanda Sharp started Frieze Art Fair in 2003 and launched a New York edition this year, the new-look format was a way of keeping the event fresh.

"We think it's always good to innovate and try new things, as it keeps people interested and excited and us interested and excited too," he told Reuters.

"What we thought we could do with (Frieze Masters) was to animate all of this art that was radical when it was made."

RIVAL FAIRS

Rival fairs like PAD London, held in the exclusive Berkeley Square from October 10-14 and best known for showcasing 20th century art and design, will also delve into the past.

Galerie Mermoz, based in Paris, will present tribal art including a ceremonial head of Hacha representing the god Xipe Totec, dated 450-750 AD, from Mexico.

Modern PAD highlights include Alexander Calder's 1943 "Constellation with Red Knife" valued at $3.5 million.

Sotheby's offers Richter's "Abstraktes Bild (809-4)" for $14-19 million at its contemporary auction on October 12.

The painting has the added buzz of belonging to guitarist Eric Clapton who bought it and two other works by the German artist for $3.4 million in 2001.

That kind of price rise underlines how the top end of the art market has largely defied broader economic gloom.

Auction records have tumbled as buyers from the Middle East, Russia and China snap up top lots for private collections, long-term investments or to fill new museums and galleries.

"There's a lot of confidence in London at the moment," Slotover said of the art market. "London is a brilliant gateway to the rest of the world."

Not everyone is celebrating the boom.

Benedict Silverman, whose $160 million collection of works from early 20th century Germany and Austria is being sold for charity, blamed "speculators" for driving prices higher and making life difficult for collectors like himself.

"The prices paid these days are for trophies, not for art," he said.

"I think there is a bubble and I can't wait for it to break as real collectors are interested in the art, not the price." (Reporting by Mike Collett-White, editing by Paul Casciato)

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