Rubens painting worth £3.5m revealed under 140 years of dirt and varnish

‘It’s one of those moments that you have a couple of times a year when you walk in, and you have this wonderful instant reaction of glee,’ says expert at Sotheby’s

A Sotheby’s technician with the Rubens portrait, which was until recently hidden away in a private collection, unknown for much of the 20th century (PA)

A Rubens painting that could command £3.5m at auction has been discovered, after gathering dust in a family collection for nearly 140 years.

The Portrait Of A Lady was revealed after layers of dirt and varnish were carefully removed by experts at Sotheby’s in London, where it will go under the hammer with a £2.5m-£3.5m estimate.

The masterpiece, which dates back to the 17th century, was exhibited at the Royal Academy in London in 1902 as a work by Rubens, but its origins had been “forgotten about”.

It remained in a family collection for 139 years until an anonymous buyer purchased it for £78,000 in 2017, when it was catalogued as being from the workshop of Rubens. That means it was thought to have been painted by one of the Old Master’s assistants.

The buyer hoped it was the real deal and took it to Sotheby’s for experts to have a look. He is now selling the work.

Andrew Fletcher, head of the auction house’s department for Old Masters paintings, said: “It was quite dirty, with a hundred years of dirt and old varnish on it,” but once it was clean, “this rather wonderful Rubens was revealed.

“It’s one of those moments that you have a couple of times a year when you walk in, and you have this wonderful instant reaction of glee.”

Using an infrared camera, experts spotted “hidden details” which indicated changes the artist made while painting, which Mr Fletcher said helped prove the painting’s authenticity, “as opposed to it being a slavish copy”.

“There is one enormous change in the sky where the red curtain descended … Rubens obviously wasn’t happy with that so pushed it back up and included more sky,” he said.

“And to the contour of her dress, you can see that he painted it one way first and then … he’d broadened her shoulders and the contour of her dress.

“And in a more minor way you can see lots of little changes in his painting of the fingers and hands.”

He described the portrait of a young woman in a black dress and cloak as “very majestic”, and said she had a “wonderful presence”. She looks “out slightly out the corner of her eye with a little bit of a grin”, he added.

“There’s a real sense of character to her face even though she’s actually posed in quite a formal way.”

The painting will go on auction for Sotheby’s on 29 July, the first major evening sale in London since the coronavirus lockdown began in March.

Reporting by PA