Are Lab-Created Diamonds Truly Eco-Friendly?
The marketing copy reads well. Grown in a lab, no mines, no scarred earth, no displaced communities. A diamond with a clean conscience. Retailers lean hard on this story, and buyers accept it. But the environmental credentials of lab-created diamonds depend almost entirely on one factor that rarely makes it into the advertisement: where the electricity comes from.
A 2024 peer-reviewed study in Nature’s Humanities and Social Sciences Communications found that lab-grown diamonds produced with clean energy result in 0.028 grams of greenhouse gas emissions per carat. Mined diamonds produce 57 kg. That sounds like a closed case. It is not.
Two Competing Stories From Industry Data
The numbers contradict each other depending on who paid for the study. Consultancy Frost and Sullivan found that mining produces 4,383 times more waste than manufactured gems and uses 6.8 times as much water. The Diamond Producers Association commissioned a different study from Trucost. That report claimed mined diamonds emit 160 kg of CO2 per polished carat, while lab-grown diamonds emit 511 kg.
Both studies exist. Both get cited. Neither tells the full story because neither accounts for the variation in production methods across different facilities and regions.
The Grid Problem Behind Green Marketing
Production location determines environmental impact more than production method. A single polished carat of lab grown diamonds from India generates 612 kg of CO2 equivalent, according to Statista data from 2023. China follows at 523 kg per carat. The European Union sits at 260 kg. When facilities run on 100% renewable energy, that figure drops to 17 kg per carat.
Coal dependency explains the gap. ABC News reported in April 2024 that 63% of China’s grid electricity and 74% of India’s comes from coal. These two countries produce over 60% of the world’s lab-created stones.
Energy Consumption Per Stone
Growing a diamond takes power. Most facilities require between 250 and 750 kilowatt hours to produce a single rough carat. Diamond Foundry claims their process uses 25 kilowatt hours per carat, well below industry averages. Their CEO Martin Roscheisen told Fortune the energy required is about one tenth of mining operations.
But Paul Zimnisky, a diamond industry expert, noted to Fortune that companies transparent about their supply chain and renewable energy use represent a small portion of total production. The efficient operators get the headlines. The coal-powered majority produces the volume.
What Regulators Actually Said
The Federal Trade Commission sent letters to 8 jewelry marketers in 2019. The issue: environmental claims that consumers might find misleading. Companies had advertised products as eco-friendly, eco-conscious, or sustainable. The FTC stated it was highly unlikely these claims could be substantiated across all reasonable interpretations.
No fines were issued. The FTC sent warnings. The marketing continues, often with softer language that stops short of explicit environmental promises.
Facilities Running Differently
Some producers have invested in verified renewable operations. Pandora grows, cuts, and polishes their lab-created diamonds using 100% renewable energy. A finished white Pandora stone carries roughly 9.17 kg of carbon emissions per carat, which the company says represents a 95% reduction compared to mined stones of equivalent size.
Diamond Foundry built a facility in Wenatchee, Washington, drawing power from local renewable sources. They purchase carbon credits to offset remaining emissions. Their new plant in Spain runs on a dedicated 120 MW solar installation with battery storage.
Creative Technologies in Surat, India, built a 25 MW solar project across 31 acres to power their growing facility entirely.
These examples exist. They represent a fraction of global output.
Mining Companies Respond
De Beers published a 2024 sustainability report showing a 7% reduction in Scope 1 and 2 emissions since 2021. The company is financing wind and solar plants in South Africa that will supply 100% of the Venetia mine’s electricity needs. Their 2030 targets include a 42% cut in direct emissions and a 25% reduction in supply chain emissions.
Mining carries undeniable environmental costs. Disturbed land, mineral waste, water consumption. A peer-reviewed comparison found mining produces 2.63 tonnes of mineral waste per carat versus 0.0006 tonnes for lab production using clean energy. Water usage runs at 0.48 cubic meters versus 0.07 cubic meters under the same conditions.
Certification Attempts
SCS Standards developed SCS-007, described as the first comprehensive sustainability standard for diamonds covering both natural and lab-grown stones. In May 2024, ALTR Created Diamonds became the second company to receive this certification for 100% renewable energy powered production.
Saleem Ali, an energy and environmental expert at the University of Delaware, told National Geographic there is no question that lab-grown diamonds come out better on environmental measures. The qualifier matters when comparing equivalent production standards.
Market Growth Without Transparency Growth
Production volume has expanded from 2.5 million carats in 2015 to 16 million carats in 2024, according to Straits Research. That represents a 6.4 times increase in a decade. Certification and third-party verification have not kept pace with this expansion.
A buyer looking at a lab-grown diamond in a retail case has no reliable way to determine where that specific stone was made, what energy source powered its creation, or what emissions it generated. The supply chain remains opaque for most of the market.
The Honest Answer
Lab-created diamonds can carry a substantially lower environmental footprint than mined stones. The 2024 Nature study demonstrates this clearly under controlled conditions with renewable energy. But conditions are not controlled across the industry. Most production happens in regions with coal-heavy electrical grids.
The answer to the question in the title depends on which lab created the diamond. A stone from a certified renewable facility in Spain or Washington state earns its environmental claims. A stone from an unverified facility drawing power from a coal-fired grid does not.
Marketing materials rarely make this distinction. Buyers should.
