A drawing bought for £20 at an American yard sale is now expected to sell for a staggering £37 million after it was found to be a lost Renaissance masterpiece.
Experts believe the unpublished artwork, titled 'The Virgin and Child with a Flower on a Grassy Bank', was produced by German Old Master Albrecht Durer in 1503.
The 6.5ins by 6.5ins pen and black ink drawing on fine linen paper, which is signed with the initials AD, is now being sold by London art gallery Agnews after extensive research confirmed its provenance.
It came to light in 2016 when a man aged in his 60s spotted it and bought it for the modest sum at an estate sale in Massachusetts, US.
The American buyer was struck by the unframed drawing's beauty but both he and the seller believed it was a 20th century reproduction.
Clifford Schorer, an art dealer for Agnews and a Durer expert, was informed about it from an antiquarian book dealer three years ago after the new owner had tried without success to sell it.
He agreed to take a look at it himself and visited the vendor who presented the drawing to him on his dining room table.
Mr Schorer stared at it for an hour as he was blown away by its 'magnificence', instantly thinking it could be the 'real thing'.
From there, he set about authenticating the drawing, showing it to museums and experts including Dr Christop Metzger, chief curator at the Albertina museum in Vienna.
Crucially, world renowned paper restorer Jane McAusland, who also inspected the drawing, identified Durer's 'Trident and Ring' watermark.
Mr Schorer said: "I thought it was too beautiful to be false and have spent three years seeking to authenticate it.
"I have shown the drawing to almost all the international Durer specialists to build a consensus (that it is legitimate).
"I believe this drawing is rarer than Raphael's (Head of a Muse), and could fetch a record price.
"It is an extremely important addition to Durer's work, who is one of the Renaissance's biggest names, and it is a once in a lifetime find."
