The student almost became the master when La Belle Ferronniere produced a major art world row, after being erroneously identified as Leonardo da Vinci’s work. Eighty years later, the oil painting by an unknown artist was auctioned at Sotheby’s on January 27 under the listing “a follower of da Vinci.” The work, depicting a richly dressed woman, is estimated to sell for $300,000 to $500,000, a steal for anyone seeking a da Vinci original. "If it was an authentic Leonardo, it would be worth more than $250 million,” the co-chairman of Sotheby's Old Masters paintings department said. In 1929, a French-American couple wished to sell the painting for a hefty price of $250,000 to a Kansas museum after a French expert deemed the work a da Vinci. But when specialist Sir Joseph Duveen declared the painting a mere skillful imitation, the sale fell through. After a lawsuit and nearly 65 years later, another da Vinci specialist ruled that the painting was done in the mid-17th century, more than a century after da Vinci had died.