A 700-year-old piece of medieval stained glass has been found hidden under a book press at Wells Cathedral – and no one knows exactly how long it's been there.

The rare glass fragment, dating back to around 1290, was uncovered during a routine tidy-up in the Cathedral's historic Chained Library on 18 February. It was spotted by intern George Parslow while working alongside Librarian Jolene Stevens.

Tucked away beneath the floorboards, the glass was later identified as part of the Chapter House Stair window – a much-loved feature of the Cathedral that's been altered and restored multiple times over the centuries.

Experts from Wells-based conservation specialists Holy Well Glass were called in to take a closer look. Their report confirmed the glass is a sexfoil tracery piece – one of the intricate elements from the window's upper section, which now holds modern replacements.

It turns out the glass was removed for conservation work by the Victoria & Albert Museum back in 1967. But some parts, including the one just found, are believed to have been taken out even earlier during 19th or early 20th century repairs. Some were put back in the wrong place – and others, it seems, never made it back at all.

Amazingly, despite years of being hidden away, the fragment is in decent condition. It may need a careful clean and some recasing, but it's survived centuries of history and a stint under the library floor without much damage.

The find is being hailed as another jewel in the Cathedral's collection of medieval treasures – and a reminder of the delicate work that goes into preserving them.

Wells Cathedral is appealing for public support to help fund projects like this. If you'd like to help conserve more of the building's historic features, you can visit wellscathedral.org.uk/support-us, email [email protected] or call the Development Office on 01749 832214.