Antiques Roadshow guest's jaw drops at massive value for family's £20 painting

WARNING: This article contains spoilers from Antiques Roadshow.

An Antiques Roadshow guest was gobsmacked when an expert valued a painting, snapped up for a mere £20, at a staggering price.

The beloved BBC daytime show set its scene at the picturesque Swanage Pier and Seafront, where connoisseurs examined a treasure trove of remarkable items.

Among the treasures was a "beautiful" artwork by Samuel John Lamorna Birch, brought in by two visitors.

Recounting the painting's history, one of the guests said: "My uncle and aunt used to go to Cornwall on holiday and they found his studio, which is in the picture there, on the way down to Lamorna Cove and they met the artist and bought this picture from him."

Expert Alexandra Grill revealed that the back of the piece bore the inscription "The Studio, Lamorna", along with Birch's autograph and the original price tag of £20, which the owner verified as the purchase price.

"I know! Isn't that fantastic?" exclaimed Grill, clearly delighted.

Grill then delved into the life of the artist, explaining: "Samuel John Lamorna Birch was born in 1869 and he was really responsible for bringing in the second wave of artists down to Cornwall to form part of the Newlyn School.

"The first group of artists came down in the 1880s with Stanhope Forbes and it was Stanhope Forbes actually that suggested to him that he added the name 'Lamorna' to his surname, because there was another local artist called Lionel Birch and they didn't want to get them muddled up."

Grill enthused that Cornwall's lure for artists was due to a "fantastic sense of light and colour and that's really why they went down there."

She proceeded to evaluate the second artwork by Denys Law, one of Lamorna Birch's proteges as the guest commented: "They're all beautiful.

"Two of them are seascapes and this one is looking down the valley at the continuation of that stream," gesturing towards Birch's work, before noting it flowed into Lamorna Cove."

"Fantastic. And actually, he was a very good student, I would say," Grill praised and moved on to give her valuation.

"For 'The Studio, Lamorna', at auction, you'd be looking at somewhere around £2,000 to £3,000," she estimated.

Catching the guests off guard, one of them gasped, "Oh, goodness me!" surprised off-camera as the painting's owner gawked, visibly shocked.

"Really?", asked the owner, leading Grill to somewhat uncomfortably confirm that Denys Law's piece was worth "a lot less".

"But they're great to have together, aren't they? Teacher and student. A good story. It's part of the whole Cornish art history."

One guest then remembered: "Mum has always said 'Don't forget when I'm gone that that's a Lamorna Birch. It's not to go to a charity shop. It's a good painting.'

"So it's been really good just to find out a bit more about it and why she said that."

Antiques Roadshow is available to watch on BBC One and BBC iPlayer.