This is stone-cold genius. Making diamonds out of carbon dioxide from the air, solar and wind power, and rainwater:

UK millionaire Dale Vince says lab-grown gems will be ‘world’s first zero-impact’ diamonds

…

“Making diamonds from nothing more than the sky, from the air we breathe – is a magical, evocative idea – it’s modern alchemy,” said Vince. “We don’t need to mine the earth to have diamonds, we can mine the sky.”

– Jillian Ambrose, Ecotricity founder to grow diamonds ‘made entirely from the sky’

‘Sky Diamonds’ is a great name for the company, but I feel he’s missing an obvious Beatles tie-in.