New technology is both putting valuable church roofs at risk and also helping to trap thieves who strip lead off the venerable institutions.

It seems that thieves are using Google Earth aerial photographs to seek out the most valuable lead deposits on church roofs. Last year 2,500 thefts took place, described by one cleric as the “biggest asset-stripping of churches since the dissolution of the monasteries”. Is nothing sacred anymore?

But help is at hand. Nano-technology, the technology of very small things, is being used to combat the thieves. More than 30,000 of British churches have had their roofs coated in nano-paint.

Each one is a unique blend of microscopic particles and therefore police investigating thefts can identify any stolen lead sold to scrap metal dealers or the like.

Apparently stripping lead is a lucrative business. At its peak it was fetching £1,300 a ton.

That is a far cry from my childhood days when I remember the odd little slice of lead was taken off roof flashing to make weights for fishing lines. Hardly grand larceny.