How are diamonds grown in the lab?

Diamonds have always stood for beauty and durability. But for us, it’s not just about how a diamond looks, but also where it comes from and the conditions under which it is made.

That’s why at Maren Jewellery we use lab-grown diamonds. They have the same chemical and physical properties as naturally formed diamonds, but instead of being mined, they are grown in a laboratory under controlled conditions.

Here, we show you how this process works, where our lab-grown diamonds are created, and why traceability plays an important role for us when selecting our materials.

Our lab-grown diamonds come from our partner Fenix Diamonds and are grown in India using the so-called CVD process. CVD stands for "Chemical Vapour Deposition."

In this process, a diamond grows layer by layer under controlled conditions. The starting point is a thin piece of diamond crystal, onto whose crystal lattice carbon atoms are deposited. At high temperatures and with the help of a plasma, this gradually forms a larger diamond crystal.

After growth, further processing steps follow until the rough diamond becomes the cut lab-grown diamond that we use for our jewelry.

Fenix Diamonds carries out the manufacturing process from crystal growth to cutting and polishing within its own supply chain.

Our lab-grown diamonds are produced by Fenix Diamonds in India. Every diamond is traceable back to its origin.

Because the various production steps take place within Fenix’s own supply chain, it is possible to document the journey of our diamonds transparently, from crystal growth to the cut stone.

This transparency is an important reason why we work with Fenix Diamonds: for the materials used in our jewelry, we want to know as precisely as possible where they come from and the path they have taken.

Fenix Diamonds' production sites are regularly reviewed as part of independent SMETA 4-Pillar audits.

SMETA stands for "Sedex Members Ethical Trade Audit." As part of the 4-Pillar audits, areas including working conditions, health and safety, the environment, and business ethics are assessed.

What matters to us here is making the distinction clear: a SMETA audit is not a sustainability certification for the diamond. It is an audit process used to review conditions and processes at production sites.

Producing lab-grown diamonds requires energy. That is why, for us, “lab-grown” does not automatically mean that a diamond is created without environmental impact.

Fenix Diamonds invests in expanding renewable energy for production and uses solar power, among other things. For us, this is an important aspect when selecting our partner and at the same time a topic we want to address transparently: producing a lab-grown diamond also requires resources and energy.

At Maren Jewellery, we have consciously chosen to use lab-grown diamonds instead of newly mined diamonds for our jewellery pieces .

Lab-grown diamonds have the same chemical composition and the same physical properties as naturally formed diamonds. They are equally impressive for their exceptional hardness and brilliance and can be assessed according to the same quality criteria. You can learn more about this in our journal article on the 4 Cs of diamond quality.

A key reason for our decision is that no new diamond mining is required for lab-grown diamonds. Traditional diamond mining can involve significant disruption to landscapes and ecosystems. A study we consulted on the environmental impact of diamond mining states that, depending on the data source, extracting one carat involves moving between 250 and 1,750 tonnes of earth [1].

The CO2 emissions associated with diamond mining can also vary depending on the mine and location. The study states that mined diamonds have a carbon footprint of between 57 and 160 kg CO2e per carat, with a median of 108.5 kg CO2e per carat [1].

At the same time, it is important to us to view lab-grown diamonds in a nuanced way: their production also requires energy and causes CO2 emissions. The extent of these depends, among other factors, on the production method, the manufacturing location, and the energy used. That is why we do not describe lab-grown diamonds across the board as emission-free or inherently more climate-friendly.

For us, a key advantage is that no new diamond mining is required for our lab-grown diamonds. At the same time, we can trace their origin and document it transparently. In this way, we combine the special properties of a diamond with our standards for transparency, traceability, and a more responsible use of resources.

With lab-grown diamonds, we can create jewelry where more than just design and quality matter. Origin, traceability, and the conditions within our supply chain are also part of what makes a piece of jewelry for us.

That’s why we take a close look at which partners we work with, what information we have about our materials, and where we can continue to improve our processes.

Because for us, responsible jewelry does not mean promising perfect solutions. It means choosing materials consciously, making supply chains traceable, and speaking transparently about what we already know today and where further development is still needed.

(1) Dr. Gbemi Oluleye – Research Fellow, Centre for Environmental Policy, Imperial College London, "Environmental Impacts of Mined Diamonds", 2021.