Old painting bought online for just £390 is worth £50,000

The BBC's Fake or Fortune has unearthed an incredibly valuablework of art that was snapped up online for just £390. The work is apparently a lost portrait of a child by Willem de Kooning, which is worth around £50,000.

The painting had been for sale on a second-hand website for 450 euros (about £390). A Belgian couple, Jan and Chris Starckx, liked the look of it, regardless of the artist, so bought the painting. They then approached the programme, presented by Fiona Bruce and featuring art expert Philip Mould, to see whether it was a fake or worth a fortune.

The programme took the painting to Miami, so it could be examined by an art expert side-by-side with a de Kooning painting from around the same time. They also examined the pigments used in both paintings and discovered they were identical. After further research, the painting was declared to be real.

Fiona's greatest discoveries

This must be getting a bit old hat for Bruce, because by presenting Antiques Roadshow for eight years - and several series of Fake or Fortune - she has seen some incredible discoveries. Five of the most fantastic are:

1. In 2011, an old bronze pot that had been used as a doorstop was identified as a13th century Chinese vase - the oldest bronze ever seen on the programme. It was valued at up to £15,000.

2. In 2011, a woman saw one of the show's jewellery experts talking about a picture of jewellery and waxing lyrical about the items depicted. He said they were his 'most wanted' items but had given up looking for them. A woman recognised one of them as a broken brooch lying around in her jewellery box. She took it on the programme and it was valued at £10,000.

3. In 2010 an old Sunbeam Talbot was brought along for valuation. It had been used by a farmer to pull his pigs to market, but since then had been identified as the car driven by Stirling Moss when he won the Charles Ferro Trophy in the Monte Carlo Rally in 1967. It was valued at £50,000.

4. A priest brought along a painting he'd picked up for £400 at an antiques shop. It was identified as a £400,000 Anthony van Dyck portrait, and the priest said he was considering selling it on order to invest in some new church bells.

5. In October last year, the programme came across the most valuable item ever to be brought along for examination: the FA Cup. It was valued at £1 million (although viewers were unimpressed with the valuation on the grounds it was hardly a shock that the cup was so valuable).