A Dash Of Olive Oil May Preserve Decaying British Cathedral | WAMU 88.5 - American University Radio

NPR : News

Filed Under:

A Dash Of Olive Oil May Preserve Decaying British Cathedral

The British have some stunning cathedrals, and York Minster, in the north of England, is one of the most magnificent of all.

Construction on it began 800 years ago, and a mere two-and-a-half centuries later, work was complete.

The result was one of Europe's largest Gothic cathedrals and one that's had a rough ride through history: It's been pillaged and looted, and damaged by devastating fires and lightning strikes.

Today, there's another threat: acid rain. As a result, the cathedral's stones are decaying.

British scientists and archaeologists have teamed up to try to find a solution. One promising possibility may be as close as the kitchen cupboard: olive oil.

The medieval craftsmen who built York Minster used rock from a nearby quarry. It's a type of limestone particularly vulnerable to damage by atmospheric pollution.

And because limestone has a memory, it's not just pollution created by this modern, car-crazy age. Locked within the stones of York Minister are the residues of pollution churned out in the 19th century by the factories and power plants of Britain's Industrial Revolution.

Those residues slowly permeate the surface of the stone with alarming effect.

"The salts actually build up in the micro-structure of the stone and eventually crack it and large features will start to fall off the building," says Karen Wilson of Cardiff University in Wales.

The Search For A Protective Coating

She heads a research team trying to develop a protective coating for York Minster and other ancient limestone buildings.

They want something that's water-repellent and keeps out that acid rain. They also need it to let the limestone breathe, allowing the nasty stuff from the Industrial Revolution to escape.

Protective coatings have been tried before, over the last century or so. One idea was to oil York Minster. One experiment used linseed oil, but this damaged and discolored the stone, making it darker.

But it did give Wilson and her team an idea. They, too, turned to common household products and came up with olive oil. Its main component is oleic acid.

"The nice thing with oleic acid," Wilson says, "is that it has one end ... which will selectively react with the stone, and then the other end — which is a very long hydrocarbon chain — will give you the hydrophobic properties to repel the water."

The oleic acid gets mixed with another substance to create the protective coating.

Tests have been carried out using samples of the cathedral's stone. Wilson says it's early days, but the results are looking good.

One of the world's greatest Gothic cathedrals somehow survived all that pillaging and all those fires.

Now, maybe, it will stand for another 800 years — thanks to a little salad dressing.

Copyright 2013 National Public Radio. To see more, visit http://www.npr.org/.

NPR

Book Review: 'Angels Make Their Hope Here'

Alan Cheuse reviews Angels Make Their Hope Here, by Breena Clarke.
NPR

Fruit Recall Hits Trader Joe's, Costco, Wal-Mart Stores

The recall applies to "certain lots of whole peaches (white and yellow), nectarines (white and yellow), plums and pluots" from a California packing company, the FDA says.
NPR

On Immigration, America's Concerns Are Fiery But Fleeting

In a recent Gallup poll, most named immigration the biggest problem confronting the nation. But past periods of heightened worries have been brief — and haven't brought about solutions.
NPR

9/11 Commission Issues An Update On Anniversary Of Report

Saying that the world has changed "dramatically," the report's authors write that al-Qaida groups have spread, and the threat for cyberterrorism has grown.

Leave a Comment

Help keep the conversation civil. Please refer to our Terms of Use and Code of Conduct before posting your comments.