Stone me! Can this eco tycoon REALLY conjure up ‘green’ diamonds… out of thin air? 

Making diamonds out of thin air all sounds rather pie in the sky. But that was the gem of an idea dreamed up by green energy tycoon Dale Vince.

He has likened the concept behind his so-called ‘Sky Diamonds’ to alchemy, the medieval pseudoscience of turning base metals into gold.

As unlikely as all this sounds, his top secret process works, apparently, with his stones recognised by the International Gemological Institute, which certifies gems and jewellery.

Precisely how is a mystery, however, as his team insist: ‘Only a few people know and we plan to keep it that way.’

If this all suggests some sort of sorcery, Mr Vince says he ploughed £5million into the unlikely-sounding scheme, and his investment is protected by various global patents. He hails his approach as eco-friendly, and calls it ‘bling without the sting’.

Natural diamonds were formed billions of years ago deep within the Earth’s crust under conditions of intense heat and pressure that cause carbon atoms to crystallise.

However, getting to them deep beneath the Earth’s surface causes environmental damage.

Mr Vince, 59, says his method begins with sucking carbon dioxide from the atmosphere with a machine. 

It is liquefied and purified, then mixed with hydrogen, obtained from rainwater by a chemical process called hydrolysis. The carbon dioxide and hydrogen are then made into methane gas.

This is pumped on to ‘diamond seeds’ – 5-7mm square thin pieces of diamond – at his laboratory in Stroud, Gloucestershire. 

The carbon in the gas attaches to the seeds and forms the crystal structure of a diamond. 

The ‘Sky Diamonds’ take two weeks to grow in balls of plasma kept at about 8,000C – roughly the temperature of the surface of the Sun.

As baffling as it sounds, it is not new for diamonds to be ‘grown’ in a lab using a chemical technique. They are chemically, physically, and optically the same as those grown beneath the Earth’s surface.

But Mr Vince, a former new age traveller who in 1996 founded Ecotricity, the world’s first green energy company, claims his gems will be the most eco-friendly.

He said: ‘Ten years ago, I was thinking about how we might take carbon out of the atmosphere and lock it up into an enduring form. The most enduring form of carbon known to mankind is the diamond – so, what if we could turn atmospheric carbon into a diamond?

‘We wanted a clean process. We use only the wind, the sun and the rain and excess carbon dioxide. Everything that we use came from the sky. There’s no waste products and no pollution – unlike diamond mining, which causes pollution, leaves huge craters and generates carbon emissions.’

He says his team can produce around 200 carats of diamonds a month, but is preparing to scale up production. The stones are expected to sell for around the same as natural diamonds.