In the first 10 days of September, shares of Sotheby's fell 14 percent. "Beautiful Inside My Head Forever," a highly anticipated sale of works by megastar Damien Hirst, was seen as a vital indicator of the strength of the contemporary art market—and investors doubted the auction house would be able to meet the $117 million minimum goal it set for the London event.

There was good reason to be skeptical: Financial markets were already suffering, and so far in 2008, 30 out of the 43 Hirsts auctioned off had sold at the lower end of estimates, according to a report published by research company ArtTactic. Several of the most expensive sold for substantially below their lower estimates.

But on Monday evening, as the collapse of Lehman Brothers and sale of Merrill Lynch led Wall Street toward its worst single-day loss in seven years and insurance giant A.I.G. teetered on the brink of failure, Sotheby's was bringing the hammer down on an $18.7 million bullock preserved in formaldehyde.

By the end of the evening, Sotheby's had realized $127 million in sales, sweeping past the night's presale high estimate.

The auction house's salesrooms were filled to capacity, with all of the nearly 700 tickets reserved beforehand. When the sale concluded Tuesday evening, 218 lots had been purchased for a total of $198 million—10 times the previous single-artist record, set in 1993 for 88 works by Picasso.

The Golden Calf, a white bullock sunk in formaldehyde with 18-karat gold hoofs and horns and a gold disk crowning its head, set an auction record for Hirst. The Kingdom, a tiger shark in formaldehyde, made $17.2 million, more than double the high estimate. A glass case filled with fake diamonds, Fragments of Paradise, went for $9.4 million—around five times the presale estimate.

"I think the market is bigger than anyone knows," Hirst said, in a message relayed by Sotheby's on Tuesday.

For Hirst collectors in particular, the show's success allayed fears that the artist's recently high level of production would pull prices down; it also shows that, at least for now, there is no sign of Hirst falling out of fashion. Not only were sales stunningly strong, but the 11-day presale viewing attracted more than 21,000 visitors, a Sotheby's London record.

The auction's triumph suggests that the current art market is invulnerable to a general economic slowdown, in part because purchases of high-end art tend to involve long waits for specific works or pieces by in-demand artists—not impulse buys easily discouraged by downbeat headlines. Plus, collectors are typically cash-rich individuals or institutions, and today more of them are from Russia and the Persian Gulf States.