An unfinished masterpiece by Titian partly overpainted some 400 years ago and recently uncovered following decades of cleaning, will be offered in Christie's sale of Old Master Pictures on December 8. The Portrait of a Lady and her Daughter, the only known work by Titian to show a mother and daughter, is expected to top 5m. It is thought that the subjects are Titian's daughter Emilia and one of his granddaughters. The painting probably dates from the 1550s, but was never completed, though both heads are fully realized. Emilia is shown as a mature and beautiful woman. The daughter, whose brown hair is dressed with seed pearls, has an earring of amethyst. The canvas was reworked soon after Titian's death in 1576 by one of his pupils, as Tobias and the Angel, probably to ensure a sale. The Lady was given wings and became the Archangel Raphael, while the daughter was given a male hairstyle to become Tobias. The Tobias and the Angel was first recorded in the mid-18th century when it was in the famous Barbarigo Collection in Venice. This collection, which included other unfinished works by Titian, was sold in 1850 to Czar Nicholas I of Russia, and the pictures, including this work, entered the Hermitage. However, a few years later, the czar was advised to dispose of nearly 3,000 pictures, and this work was acquired by Russian aristocrat Count Tyszkiewicz of St. Petersburg, in whose family's collection it remained until 1913. By the 1920s, the painting belonged to picture dealer Ren Gimpel. Though in late middle age, Gimpel joined the French Resistance after sending all his pictures to hiding places in London. He revealed their location to no one. He was captured and sent to the slave labor camp at Neuengamme and perished in 1944. It was some time before his sons, who had also fought in the Resistance, were able to locate the pictures. The Titian, along with many other paintings, was discovered in a garage in Bayswater in 1946. Gimpel's son Jean had the Tobias and the Angel x-rayed by Stephen Rees-Jones at the Courtauld Institute Technology Department in 1948, when the underlying composition became apparent for the first time. The restoration process took nearly 20 years and it was only in 2001 that the original portraits were revealed. The picture was then the major rediscovery of the Titian exhibition of 2003 in Madrid. Tiziano Vecellio, called Titian (circa 1485-1576), was born at Pieve di Cadore, Italy, and moved to Venice when he was 10. He succeeded Giovanni Bellini as painter to the Republic of Venice in 1516 and soon became famous across Europe, in particular for his skill as a portraitist. He provided direct inspiration for Vel zquez, Rubens, Rembrandt and van Dyck, as well as modern and impressionist artists like Monet and Renoir.

Auctions: An uncovered Titian at Christie's

The painting probably dates from the 1550s, but was never completed; it's expected to top 5m.