Pensioner's treasure at the bottom of her bag

The brooch had been lying in the bottom of jewellery box for around 20 years when it was the subject of an item on 'Antiques Roadshow' in March. Photo / Thinkstock

An English pensioner who almost sold off an unwanted brooch for £10 before realising its true value thanks to Antiques Roadshow has seen the item fetch more than £36,000 (NZ$67,500) at auction.

Jill Cousins, from Market Harborough, Leicestershire, was said to be "jumping for joy" after a private collector from the London area snapped up the object, which had been expected to pull in around £10,000.

Created by Victorian designer and architect William Burges, the adornment had been lying in the bottom of jewellery box for around 20 years when it was the subject of an item on Antiques Roadshow in March.

The "most wanted" appeal by Antiques Roadshow jewellery expert Geoffrey Munn was broadcast just two days after Mrs Cousins had forgotten to put the brooch in her bag as she headed to a local market, where she would have been prepared to sell it for around £10.

Mrs Cousins, 68, recognised a sketch of the brooch, which is thought to have been made in the 1860s, and then took it to her local auctioneer, who confirmed her good fortune.

Described as "one of the most important art historical objects ever to be seen" on the long-running BBC programme, the brooch went under the hammer for £31,000, but other costs, including buyer's premium, took the successful bidder's total bill to £36,580.

Speaking after the sale in Market Harborough, auctioneer Mark Gilding said: "It's an outstanding price. When I woke up this morning I thought it might make between £10,000 and £20,000. £31,000 is more than I could have imagined."

- AAP