LONDON (Reuters) - Christie's will offer for sale what it calls a Rembrandt "masterpiece" in December, and expects to fetch up to 25 million pounds ($41 million) in what would be an auction record for the artist. The painting, titled "Portrait of a man, half-length, with his arms akimbo," was painted in 1658 and has been unseen in public for nearly 40 years. The last time it was sold at auction was in 1930 when it fetched 18,500 pounds, or today's equivalent of nearly six million pounds. "We look forward to welcoming international collectors and institutions from around the world to what will be a landmark auction in the history of the European art market on December 8 at Christie's in London," said Richard Knight, co-head of Old Masters and 19th century art. With a pre-sale estimate of 18-25 million pounds, one of the most valuable paintings to come to auction for some time will be seen as a key barometer of the strength of the art market, which has contracted sharply during the financial crisis. The work will go on public display from December 4-8. HARD TIMES Soon after the painting was sold at auction in 1930, it was acquired privately by George Huntington Hartford II, an art collector and heir to a large fortune. Hartford donated the work to Columbia University in 1958, and when students occupied the president's office in 1968 during a demonstration, it was removed and put into storage. It was sold again privately in 1974 and has been in the same collection since. It was last seen in public in 1970 at the "Rembrandt After 300 Years" exhibition in Detroit. In 1658, when the work was painted, Dutch master Rembrandt was forced to sell his house in Amsterdam and move to a smaller studio, having been declared bankrupt two years earlier. Only one other painting by the artist dated from 1658 is known to exist: "Self-portrait" in the Frick Museum in New York. According to Christie's, the auction record for a Rembrandt is 19.8 million pounds (then $29 million) set at Christie's in London in 2000. The top price at auction for an old master picture was 49.5 million pounds ($77 million) for "The Massacre of the Innocents" by Peter Paul Rubens set at Sotheby's in London in 2002. Also on offer at the Christie's December sale will be "Saint John the Evangelist" by Italian artist Domenico Zampieri, also known as Il Domenichino. http://www.reuters.com/article/artsNews/idUSTRE58H0QP20090918 The Baroque work has been valued at 7-10 million pounds.