THE Church of England is using nanotechnology – the science of very small things – to fight thieves who strip lead and other valuable metals from the roofs of its ancient buildings.

More than 30,000 of Britain’s 44,000 churches have had their roofs coated in a layer of “nanopaint”, which is visible only under ultraviolet light.

Each church has a different blend of microscopic particles, giving its metal a unique “label”. This enables police to identify church lead found in any haul of suspect scrap, even if it has been melted down.

Tewkesbury Abbey and Gloucester and Manchester cathedrals are among those whose roofs have been given the treatment.

Recently, church authorities scored a victory in the battle against thieves with the conviction of three men for stealing lead from the roof of St Leonard’s church in Colchester, Essex.

They were caught after police identified the lead stolen from the church on sale at a scrapyard by using the new labelling system.

The nanotechnology system, called SmartWater, has been developed by Phil Cleary, a former police officer, and his brother Mike, a fellow of the Royal Society of Chemistry.

The number of insurance claims for metal thefts from churches has risen from just 12 in 2002 to more than 2,500 last year – attacks described by Peter Walley, chaplain to the bishop of Lichfield, as “the biggest asset-stripping of churches since the dissolution of the monasteries”.

Walley’s comments follow 70 thefts from Lichfield diocese churches last year alone. Criminals have even used aerial photographs on Google Earth to locate the most lucrative hauls.

Church insiders say the financial impact of such thefts has been severe. Individual insurance claims often exceed £100,000, despite the value of the lead stolen being a fraction of that, because of the further damage done by thieves as they rip off the metal.

The demand for scrap is driven by world prices. Those for lead and copper soared to record levels last year with scrap lead peaking at £1,300 a ton. Metal prices fell when the recession hit, but are now picking up again strongly.

Most churches are insured by Ecclesiastical Insurance, which is so concerned at the losses that it recently sent every church a SmartWater kit and warned vicars and bishops it would pay out no more than £5,000 if they failed to use it on their roofs.

A spokesman for Ecclesiastical Insurance said metal theft had become the number one reason for claims.

Times Recommends

• Oh no, Mr Darling: you have failed
• BBC survives dogfight over Kennel Club expose
• Where the Rosetta belongs can’t be set in stone