The Science of Uncovering Forged Paintings

With Basquiats, Modiglianis, and Picassos going for upwards of $100 million, the stakes have never been higher.

By Stephen Wallis

Sep 17, 2018

https://www.townandcountrymag.com/leisure/arts-and-culture/a23086822/art-fraud-forgery-science/

There’s an old joke among art market veterans that says the thicker the file of supporting documents for a painting, the more likely it is to be a pants-on-fire fake. These days, in a world in which Basquiats, Modiglianis, and Picassos can top $100 million, the stakes have never been higher for prospective buyers, who want all the evidence they can get that the works they’re considering are exactly what they think they are. Less willing to rely solely on the opinions of experts—many of whom have stopped doing authentications, out of fear of being sued—collectors, dealers, and auction houses are increasingly turning to scientists.

They’re hiring people like Nica Gutman Rieppi, a technical art historian and conservator who serves as the lead investigator in New York for the firm Art Analysis & Research. The company, which also has offices in London and Austria, uses a variety of state-of-the-art tools to analyze materials and methods used to create ­paintings, determine condition and age, and help confirm attributions or detect fakes.

“Some people estimate that 20 to 50 percent of all works in the world are fakes, forgeries, misattributions, or unknowns,” says Rieppi, who notes that a large percentage of problematic works are, unsurprisingly, “found with artists who are selling at high price points.”

Rieppi says a typical day for her might begin by visiting an auction house to examine a Jackson Pollock coming up for sale, where she conducts a microscopic survey of its surface to look for, among other things, signs of artificial aging and any irregularities with the signature. (She has seen more than one fraudulent Pollock on which his name was misspelled.)

Later on she might be in her lab, doing infrared, X-ray, or ultraviolet fluorescence imaging on a painting that might be a Rembrandt “to determine whether it’s a work by a follower of Rembrandt from his contemporary circle, from his studio, or by the master himself,” she says.

For works made in the last 50 years or so she might employ a technology known as bomb curve analysis—she recently used it on a Basquiat—to help pinpoint the date of creation. In the late 1950s and early ’60s nuclear weapon tests caused a spike in radiation in the atmosphere, Rieppi explains, and determining the amount of radiation present in a canvas allows paintings to be dated more precisely.

One fake that Rieppi uncovered recently came to her as a Monet landscape from a private collection. The style was consistent with the Impressionist’s work, and the back of the period canvas had all the labels from galleries and exhibitions you’d expect to find. X-rays revealed an underpainting of a bouquet of roses, which wasn’t itself unusual, except that there was a layer of aged varnish on top of it, indicating that the landscape must have been painted considerably later. What cracked the case, Rieppi says, was the presence of a synthetic blue pigment that wasn’t available until 1997.

She is quick to note that AA&R does not authenticate works, it merely produces critical supporting, or damning, evidence. “We provide information that’s an aid for authentication, ruling out anomalous materials or techniques that are inconsistent with an artist’s work,” she says. “Forgers are getting more creative, and they’re aware of the science, but there are some things that they just can’t fake.”