Scholars believe one of the paintings was commissioned by Florimond Robertet, a top administrator in the court of King Louis XII of France, before da Vinci left Milan in 1499. The other painting remained in the artist’s studio and was listed in its inventory after his death, Kemp said. “Technical analysis shows that Leonardo worked simultaneously on both pictures,” said Kemp, who authored several books about the painter, including one about the Yarnwinder Madonnas. “We can see from the under-drawings that he was very actively involved. The hair, the moist eyes—we can tell it was Leonardo.”
The Madonna of the Yarnwinder entered the Buccleuch family collection in 1767, with the marriage of the third duke to Lady Elizabeth Montagu, who inherited a substantial art collection from her parents, the Duke and Duchess of Montagu, according to the museum. They had purchased the painting at auction in Paris in 1756. While it is attributed to da Vinci at the National Galleries of Scotland, the museum acknowledges that his direct involvement has been debated. “It seems likely that the overall design, and the execution of the figures and the foreground rocks, are entirely or largely his,” according to exhibition materials. “The background landscape is less characteristic, and was probably added by another artist. Technical examination has revealed landscape features and small figures not visible on the surface. That some of these reappear in early copies of the composition supports the idea that the background may have been left unfinished by Leonardo and completed only later.” The Buccleuch Madonna was included with Salvator Mundi in a exhibition, “Leonardo da Vinci: Painter at the Court of Milan” at the National Gallery in London in 2011-2012. That exhibition attributed the painting to both da Vinci and an “unknown 16th-century painter” who “seems to have completed the landscape background,” according to the exhibition materials. Kemp, on the other hand, listed both versions of The Madonna of the Yarnwinder as by da Vinci in his book, Leonardo (Oxford University Press, 2004), and acknowledges that a studio was involved. “It would be absolutely considered to be a Leonardo, even if not every piece of brushwork is by Leonardo himself,” he said. Entrusting minor, monotonous details to assistants was a common practice in the studios of Old Masters, although unlike Titian and Rubens, Da Vinci kept it small scale. “Not like Jeff Koons,” said Robert Simon, an art historian and dealer who was part of a consortium behind the rediscovery of Salvator Mundi. “At one point, there were one or two students working with him at a time. He famously didn't finish many projects.”
No more than 20 paintings attributed to da Vinci have survived, and both Yarnwinder Madonnas “fit in between 15 and 20,” Simon said. “It depends on who you ask and how you define authorship.” How the subtleties of attribution would impact the price should either work ever come to the market is an open question. Experts agree that each would command extraordinary prices, though unlikely as high as that of Salvator Mundi, which was acquired by the Abu Dhabi Department of Culture and Tourism for the emirate’s new Louvre Abu Dhabi museum. Otto Naumann, an Old Master dealer in New York, said either painting could draw US$150 million or $200 million following the historic sale of Salvator Mundi on Nov. 15. “I joked to Francois,” Naumann said, referring to Francois de Poortere, head of Christie’s Old Masters department, whose client was the underbidder for Salvator Mundi, “why don’t you get both of them in the same auction?” Some scholars believe a third exists—also privately owned. Carlo Pedretti even put it on the cover of his 2014 book, The Yarnwinder Madonna of Leonardo Da Vinci: The Three Versions for His First French Commission (CB Edizioni; bilingual edition, 2014).