A portrait of William Shakespeare, claimed by many to have been painted during his lifetime, is a 19th-century fake, the National Portrait Gallery announced last night.

　　The discovery is the first step in a year-long study of the six works with the best claim to be contemporary portraits of the playwright.

　　The results will be revealed by the gallery early next year. If all six are fakes or copies, the popular image of a balding Shakespeare with wispy moustache and beard will be thrown into serious doubt.

　　The fake unmasked yesterday is the "Flower Shakespeare", owned by the Royal Shakespeare Company and displayed at its headquarters in Stratford-upon-Avon. The Flower family of brewers gave it to Stratford in 1895.

　　Though the unknown artist painted the inscription "Willm Shakespeare 1609" in the top left corner, the gallery said yesterday the picture might have had more to do with a 19th century "Del Boy".

　　From microscopic examination of pigments in the paint, the gallery says the picture, on a wooden panel, was painted between 1818 and 1840. Its first recorded owner, in 1840, lived in the TV rogue's home of Peckham, south London.

　　The investigation has also confirmed an earlier finding that the Bard's portrait was covering a much earlier religious painting. The gallery has identified it as a minor Florentine work of the 1540s, showing the Madonna and Child with John the Baptist. Shakespeare the man remains an enigmatic figure.

　　The most widely accepted likenesses of him are a bust at his burial place of Holy Trinity, Stratford-upon-Avon, and the engraved portrait that appeared on the First Folio of his collected plays, seven years after his death in 1623.

　　The First Folio illustration was by a young engraver from the Low Countries called Droeshout, and a number of scholars have argued that he copied the likeness from the "Flower Shakespeare". Others have always maintained that it is a fake.

　　Tarnya Cooper, who is in charge of the investigation, said: "It certainly isn't what many have purported it to be and the RSC has championed it as the original from which Droeshout made his copy. It is clearly the other way round.

　　"It is fantastic that we can be so categorical. But it doesn't get us any closer to answering the question 'What did Shakespeare look like?' "

　　The gallery's key finding was that two pigments in the "Flower Shakespeare", chrome yellow and French ultramarine, were not available until 1818 and 1826 respectively. Experts also ruled out the possibility that they had been used to repair an older work.

　　The gallery team will now carry out similar investigations into the other five lifetime portrait "contenders". The results will be presented at an exhibition, Searching for Shakespeare, next March.

　　The two pictures with the best claims are the undated "Chandos Shakespeare", the first painting given to the newly founded gallery in 1856, and the "Grafton Shakespeare" at the John Rylands Gallery in Manchester, which bears an inscription saying it was painted in 1588, when the playwright was 24.