There is a question that does not get asked often enough in the lab grown diamond industry.
Not where was this diamond mined. We know the answer to that, which is why we chose lab grown in the first place. But where was this diamond grown? And what powered it?
Because here is the uncomfortable truth that the industry has been slow to address. The shift from mined to lab grown diamonds was the right call. But it was not the complete answer. And at Diamonds of Cornwall, we think it is time to say that plainly.
The Energy Paradox
Lab grown diamonds are created using either Chemical Vapour Deposition (CVD) or High Pressure High Temperature (HPHT) technology. Both methods require extraordinary amounts of energy to maintain the extreme conditions needed to grow a crystal atom by atom, reaching temperatures hotter than the surface of the sun.
Producing a single carat of diamond typically requires between 250 and 750 kilowatt hours of electricity. To put that in context, the average British household uses approximately 52 kilowatt hours per week. Growing one carat of diamond consumes as much energy as a typical British home uses in five to fourteen weeks.
When that energy comes from renewable sources, the environmental case for lab grown diamonds is compelling. When it comes from coal, as it does for the majority of global production, the picture changes entirely.
Over 70% of the world's lab grown diamonds are currently produced in China and India, where coal and fossil fuels remain the dominant energy sources. In 2023, India's production of lab grown diamonds carried a carbon footprint of 612 kilograms of CO2 equivalent per carat. China's was 523 kilograms per carat.
The label lab grown is not enough. It never was.
What We Are Building
Diamonds of Cornwall was founded to answer a question that has been sitting unanswered at the heart of the lab grown diamond industry for years. What does a truly sustainable diamond actually look like?
Our answer: it is grown in Cornwall, powered by 100% renewable Cornish energy, using our own proprietary MPCVD reactor technology. This is the luxury standard of diamond growth, free from the metal contamination risks of HPHT and the quality compromises of standard CVD.
And it goes further than that. Our diamonds are carbon negative. We use carbon captured directly from the atmosphere as part of the growth process itself. We do not just offset our emissions. We remove more CO2 from the atmosphere than our production creates. The diamond that arrives in your ring has left the planet cleaner than it found it.
Why Cornwall
Cornwall is not an obvious location for a diamond growing facility. Which is precisely why it is the right one.
The county has one of the most consistent renewable energy profiles in the UK, with wind, solar, and tidal energy. It sits outside the fossil fuel dependency that burdens most of the world's diamond production. And it carries a heritage of craftsmanship, innovation, and doing things properly that feels entirely right for what we are trying to build.
We are not a factory. We are not a volume operation. We are a small, precise, technologically advanced producer making something genuinely extraordinary. A diamond you can hold in your hand and know, with complete certainty, exactly where it came from, how it was made, and what it cost the planet.
The answer to that last question is: less than nothing. It gave something back.
What Comes Next
This blog is the first of a series in which we will explore the science, the ethics, and the story behind Diamonds of Cornwall and behind the wider lab grown diamond industry that we believe needs a more honest conversation than it has been having with itself.
We will write about the difference between diamond growing methods and why it matters more than most people realise. We will write about the carbon negative standard and what it actually means. We will write about what it means to build something in Britain and why that distinction matters in 2026.
We will, as always, try to say the true thing plainly.
We are Diamonds of Cornwall. Grown in Cornwall. Powered by purpose. Built from thin air.