A sultry 1955 blue-and-orange canvas by Mark Rothko sold tonight for $34.2 million at Christie's International in New York at a contemporary and postwar auction that shattered records. All-time high prices were set for painters Richard Prince, Lucian Freud and Ed Ruscha, photographer Thomas Struth, mixed- media maven Jeff Koons and Chinese contemporary artist Zhang Xiaogang. The auction totaled $325 million, midway between the presale estimates of $271 million to $373 million. A 1963 turquoise Andy Warhol portrait of actress Elizabeth Taylor sold for $23.6 million, below its $25 million low estimate. The "Liz," offered by British actor Hugh Grant, was one of the evening's disappointments, selling after lackluster bidding from just two contenders, including Alberto Mugrabi, a dealer heavily invested in the artist. The Warhol came about halfway into the evening auction, projected to tally as much as $373 million. Tomorrow night's contemporary sale is at Sotheby's, whose stock lost 36 percent of its value last week amid concern that the art market may have peaked. All prices include a buyer's premium, or commission, of 25 percent of the hammer price up to $20,000, 20 percent of the price from $20,000 to $500,000, and 12 percent above $500,000.