Demand for fine art is thriving, but it is the priciest works that are attracting most interest, art experts told CNBC, as a number of paintings sold for millions of dollars at the Frieze Masters art fair in London.
Such is the interest in top-flight art that dealers are finding it easier to sell expensive works than cheaper ones, said Clare McAndrew, head of Dublin-based research firm Arts Economics.
"It is a polarized market: the top-end is doing very well, while the middle-to-lowish-end has struggled a little bit more since 2009/10," she told CNBC on Wednesday.
"The best pieces are relatively easy to sell; it is a crazy time for some dealers, who are selling higher volumes of more expensive work and lower volumes of less expensive works… It is easier to sell items for over $1 million dollars, than for $100,000."
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The boom at the top of the market is reflected in the price tags for the art on offer at this year's Frieze Masters fair, which features ancient and medieval works alongside Old Masters and modern artists like Picasso. The event, now in its second year, runs in tandem with the main Frieze showcase, which concentrates on contemporary art from around the world.
Paintings for sale include a re-discovered work by Flemish Old Master Brueghel the Younger, which was unveiled at the fair and is under reserve for £6 million ($9.6 million).
Frieze Masters opened to "VIPs" on Wednesday, and buyers have already snapped up a Picasso and two de Koonings (a Dutch expressionist who died in 1997) for around $8 million each. Another Picasso and a work by contemporary artist Basquiat sold for over $1 million each.
"The showing by the dealers was much stronger this year; it was a much more confident offering of top-range pieces… A lot of the dealers were selling on the first day — the top dealers were paying their way on the first day," said Philip Hoffman, who heads art investment firm Fine Art Group.
Those not invited to the first day of Frieze Masters have had to wait until Thursday to visit the fair.
According to Knight Frank's 2013 "Wealth report," fine art is currently the most popular "investment of passion" among wealthy individuals — defined as those with net assets of over $30 million — topping wine, watches, classic cars and sports teams. Nineteen percent of private bankers and wealth advisers surveyed by the real estate agent said clients' investment in art rose in 2012, and 13 percent forecast a further uptick this year.
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But despite the buzz, art's performance as an asset class has been questionable. According to Knight Frank's luxury investment index, the value of fine art fell 6 percent in the 12 months to September 2013, underperforming other collectables such as jewelry and cars.
The returns on art look more respectable over the long-term, however, with gains of 182 percent over the last decade, similar to those for wine.
"Art as an investment is good for the next 10 years," said Hoffman. "I think there will be many more investors moving into the art market, as art proves that it can be a serious investment market."
—By CNBC's Katy Barnato