In this particular programme Geoffrey Munn, jewellery expert and managing director at Wartski, held up a series of watercolour sketches by William Burges (1827-1881) for brooches which he had been searching for more than 20 years. Mrs Cousins thought she had one upstairs.
In the jewellery box on her dressing table she unearthed a white and gilt metal brooch, set with a heart-shaped garnet and turquoises fashioned as forget-me-nots. It appeared to match precisely one of the sketches (which are held at the Victoria and Albert Museum in London) that Mr Munn had shown on the Roadshow.
She had inherited the brooch from her mother, who in turn had been willed it by a primary school teacher. The consensus within the family was that it was less than beautiful and Mrs Cousins, 67, a retired gate maker from Great Bowden, Leicestershire, was considering asking £10 for it at a local market later in the week.
Armed with new information and the prospect of a windfall (the potential valuation had been £10,000) she contacted her local saleroom, Gildings of Market Harborough, who were quick to confirm its links to the most celebrated of the Victorian art-architects. Mark Gilding quickly found a place for it in his safe where it has remained - save its appearance on another episode of the Roadshow filmed in Birmingham when Mr Munn was made aware of the discovery.
He described his shock at seeing the brooch in typically purple prose as "my Tutankhamun experience".
"The brooch is incredibly rare because Burges is arguably the most singular and gifted architect and designer of the 19th century and he did not make much jewellery," said Mr Munn. "Here, we have a tiny expression of his extraordinary genius distilled down into something you can hold in your hand. It is without doubt one of the most important art historical objects I have ever seen on the show."
Closer study of the 1¾in (4.4cm) brooch revealed it to be engraved with the gothic initials JPMS. Coupled with the knowledge that the watercolour sketch is inscribed Seddon, it is probable the brooch was made to mark the wedding of the architect John Pollard to Margaret Seddon in 1864. John Pollard Seddon (1827-1906), who moved in the circle of the Pre-Raphaelites, was the business partner of John Prichard of Llandaff, a friend of Burges.
The brooch is to be sold by Gildings on August 2 with an estimate available on request.
By Roland Arkell