A Rembrandt masterpiece will be going on sale at Christie's in December, and is hoped to fetch up to £25m - a record for the artist.
Art collectors should take note: the Rembrandt is one of the most valuable paintings to appear at auction for some time, and will be used as a barometer of the strength of the art market.
The 1658 classic painting, 'Portrait of a man, half-length, with his arms akimbo,' has been unseen by the public for nearly 40 years.
It last sold for £18,500 at auction in 1930, today's equivalent of nearly £6m.
The sale will take place on December 8 at Christie's, London. The painting will be publicly displayed between December 4-8.
The top price at auction for an old master picture was £49.5m for The Massacre of the Innocents by Peter Paul Rubens at Sotheby's, 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.
The Baroque work has been valued at 7-10 million pounds.
Some facts about Rembrandt's 'Portrait of a man, half-length, with his arms akimbo':
- The auction record for a Rembrandt is £19.8m (then $29m) set at Christie's in London in 2000
- 'Portrait of...' was last seen in public in 1970 at the "Rembrandt After_300_Years" exhibition in Detroit
- In the year it was painted, 1658, Rembrandt was forced to sell his Amsterdam house and move to a smaller studio after declaring himself bankrupt
- Only one other painting by the artist dated from 1658 is known to exist, Self-portrait, in the Frick Museum in New York.