It is a delicate operation that ended in disaster for Del Boy, Rodney and Grandad in Only Fools and Horses.

But yesterday, after a generous �1,000 donation from a former volunteer, the crystal chandelier at Strangers' Hall was cleaned for the first time in decades.

The 88-year-old, who wants to remain anonymous, said she spent years looking up at the 217-year-old fixture in the Georgian dining room thinking: 'I want to dust it.'

Although she stopped volunteering as a guide a couple of years ago, the Norwich woman was keen to continue to support the Charing Cross heritage attraction in some way.

She said: 'When I was here, I was usually in this room. I would sit for hours on end, gazing up there and I wanted to dust it – but I thought I had better not.

'I can't do a lot now because I'm losing my sight but I wanted to do something for Strangers' Hall, so why not get it cleaned?'

The London crystal chandelier is thought to have been made in 1795 by William Parker of Fleet Street. It was bought by the Friends of Norwich Museums in 1951 but may not have been cleaned thoroughly for at least 30 years.

Cathy Terry, curator of social history, said that without the donation from the volunteer the work would not have been done.

'It's completely unparalleled in my experience that a volunteer would want to go the extra mile and, as well as giving their time, want to support the museum in this unusual way,' she said. 'It would be outside our normal operating budget to undertake a special piece of work like this.'

While most people imagining a chandelier being cleaned would picture the famous scene from the BBC hit comedy Only Fools and Horses, this particular job required a lot more care to be taken.

Each section of the chandelier was taken down and the individual spires, glass cups and crystal droplets all cleaned separately.

Juliet Brotheridge, of Brotheridge Chandeliers, said the approach she and her husband Terry used was very different to that of Del Boy's.

'We definitely don't catch it on a blanket,' she said. 'We're removing all the glass fittings and we're carefully laying them on the table. We work quite slowly. The value of the object is worth a lot of money so we work slowly and carefully. We have allowed a day and a half for this although sometimes it takes longer because you're working with something that's very old and we might have to do some running repairs.'

The cleaning work has also helped the museum learn more about the sparkling chandelier which is the centrepiece of the dining room.

Although originally thought to be Irish glass, Mr Brotheridge yesterday told staff and volunteers it was actually London crystal.

Mrs Brotheridge also revealed the purple glass cups made the chandelier far more rare than the museum service had realised.

She said: 'Coloured glass usually comes in a lot later.'

Do you have a story about Norwich's heritage? Contact Victoria Leggett on 01603 772468.