NEW YORK (NYT NEWS SERVICE).- If French Israeli telecommunications entrepreneur Patrick Drahi, who bought Sotheby’s in June in a deal worth $3.7 billion, needed proof that auctions are unlike any other business, he got a clear introduction to that reality during this week’s unpredictable sales.

On Tuesday night, Sotheby’s saw a 40% drop in its impressionist and modern art sales compared with the equivalent sale last May. By Thursday, the auction house was heartened by the $270.6 million total of its contemporary art sale — although that, too, was 28% lower than the spring total.

To drive home the fickleness of the salesroom, Christie’s, on Wednesday, achieved an auction high for an Ed Ruscha work, fetching $52.5 million for the Prince of Pop’s 1964 word painting “Hurting the Word Radio #2.” The following night, Sotheby’s, on the other hand, couldn’t even manage to sell Ruscha’s egg yolk on silk, “She Gets Angry At Him,” from the collection of designer Marc Jacobs. Ultimately, the auction house brought the piece back to the block as the last lot of Thursday evening — and sold it for $1.7 million, below its $2 million low estimate.

“The art business is not something you can equate to any other business,” Helly Nahmad, a New York dealer, said. “They’re not selling stocks and bonds here. They’re selling fine art.”

This week’s sales provided ample evidence of why the art market continues to defy predictions and to confound those looking for reliable results. This auction season was buffeted by uncertainty around geopolitical trends. Collectors held onto their best material but, at the same time, buyers were still willing to pay top dollar for the best works that did emerge.

The auction houses suffered in the absence of any major estate sales. On the other hand, they benefited from the seemingly insatiable appetite for blue-chip works of contemporary art.

In the end, as in recent years past, dealers, collectors and the auction houses themselves were able to end the week trumpeting the results as proof of a resilient market.

“A lot of people bidding a lot of money on a lot of paintings,” said Marc Glimcher, president and chief executive of Pace Gallery. “It was a strong sale. Everybody’s happy.”

Drahi, who took Sotheby’s private in a surprise deal — and recently appointed Charles Stewart from Altice USA as his chief executive — is expected to try to streamline Sotheby’s, paring costs and emphasizing digital development.

But art experts also caution that applying standard business practices has been tried before and may continue to prove challenging. The particular alchemy of the auction world depends on personal relationships with collectors, on auction specialists with years of expertise and on the serendipity of a live sale in which bidders decide — often in the heat of the moment — to go to the mat for the same object.

That type of frenzied excitement was evident Thursday night at Sotheby’s, as bids came fast and furious for Kerry James Marshall’s “Vignette 19” park scene of 2014, propelling the final price to $18.5 million — well over the high estimate of $7.5 million (although shy of the painter’s top auction price of $21.1 million last year for “Past Times,” bought by Sean Combs).

Four bidders also competed for Marshall’s 2013 painting, “Small Pin-Up (Lens Flare),” which sold to Los Angeles dealer Stavros Merjos for more than twice its low estimate: $5.5 million.

Marshall’s mentor, the late printmaker and painter Charles White — who last year was the subject of a MoMA retrospective — also had a big night, his first in a Sotheby’s evening sale. White’s poignant and impressively large 1953 charcoal drawing went for $1.8 million against a low estimate of $500,000, setting a new auction high for the artist.

Called “Ye Shall Inherit the Earth,” the drawing shows Rosa Lee Ingram, an African American woman who became an icon of the social justice movement. In the late 1940s she was accused, with her two sons, of killing a white sharecropper. All three were sentenced to death, but after a public outcry, the sentence was commuted to life imprisonment.

The strength of these artists Thursday night was emblematic of a growing interest at auction in artists of color. An abstract painting by Norman Lewis, “Ritual” from 1962, sold for $2.8 million, a record at auction for the artist’s work.

“African American art is strong at the moment,” dealer Christophe Van de Weghe said. “The auction houses have struggled to find good material. People don’t want to sell their paintings. But when the auction houses find good things, they fly.”

At the same time, the more obvious trophies were also in high demand. Three abstract paintings went to Asian bidders. Willem de Kooning’s large-scale abstract, “Untitled XXII” — which was sold by New York art dealer Bob Mnuchin and had never before been offered at auction — went for $30.1 million, having been guaranteed by a third party to sell at $25 million.

Similarly, Clyfford Still’s 1946 “PH-399,” not seen on the market since 1970, sparked a 15-minute, three-way telephone battle before falling for $24.3 million to the same collector as the de Kooning. It had been estimated at $12 million to $18 million.

And Mark Rothko’s bright orange abstract, “Blue Over Red,” from 1953, sold for a solid $26.5 million, on a low estimate of $25 million, despite having been unloved by some visitors at the auction preview.

The different results at Sotheby’s and Christie’s contemporary sales made clear how dependent auction houses are on the quality of the consignments they are able to corral each season. All but four of Sotheby’s lots were successful, with 70% selling for hammer prices above their low estimates. The previous evening at Christie’s, 40% of the material sold below estimate.

“Maybe they had a more interesting mix of things,” said art adviser Nancy Whyte, speaking of Sotheby’s.

At Phillips earlier Thursday night, the total results were healthy, if not exactly effervescent: $108.1 million, up slightly from May’s sales.

“Everyone is a little apprehensive at the moment,” said Frances Beatty, a New York-based art adviser. “Art is very easy to buy but not so easy to sell.”

One of the most remarkable signs of nervousness in the current market is the fact that auction sales of works by KAWS ($70.6 million) were higher in the first half of 2019 than those of art market powerhouse Jean-Michel Basquiat ($65.6 million), according to Artnet’s latest Intelligence Report.

The Phillips sale included Basquiat’s red-dominated 1981 canvas, “The Ring,” showing one of the artist’s trademark boxers in polka-dot shorts triumphantly holding a spear above his head. Guaranteed to sell for at least $10 million, the painting went to art adviser Abigail Asher for $15 million, with fees.

All in all, the week attested to the vagaries of the art market, which can simultaneously seem as volatile as tech stocks and as resilient as U.S. Treasury bonds.

“It was steady,” said Hugo Nathan, a London art adviser, “No froth, no excitement, but robust results.”

He added that “The auction houses did a great job with what they had,” and that “This might be the pattern for a year or two.”

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