What is a lab-grown diamond?

Introduction: the lab-grown diamond revolution

The jewellery world is going through a genuine revolution with the rise of lab-grown diamonds. These gemstones, created by people in state-of-the-art laboratories, challenge our traditional perceptions of diamonds and open up new possibilities for consumers and the industry alike. While natural diamonds have fascinated humanity for millennia, lab-grown diamonds are the culmination of decades of scientific research and technological innovation.

Since 1954, the year that marked the history of the lab-grown diamond with the creation of the first official diamond by Howard Tracy Hall, this technology has never stopped evolving, and today it achieves a quality perfectly identical to natural diamonds. This breakthrough raises fundamental questions about value, authenticity and ethics in the jewellery sector, while offering innovative alternatives for consumers who care about sustainability and ethics.

Definition and composition of lab-grown diamonds

A lab-grown diamond, also called a laboratory diamond, cultured diamond or synthetic diamond, is a gemstone produced in a laboratory using advanced technological methods. Unlike diamond simulants such as cubic zirconia or moissanite, a lab-grown diamond has exactly the same chemical composition, the same crystal structure and the same physical properties as a natural diamond.

Made of more than 99.95% pure carbon, a lab-grown diamond has:

• The same hardness: 10 on the Mohs scale, making it the hardest known material
• The same brilliance: an identical refractive index of 2.42
• The same density: 3.52 g/cm³
• The same thermal properties: exceptional thermal conductivity

The only fundamental difference lies in their origin: natural diamonds form deep in the Earth's mantle over millions of years under extreme pressure and temperature, whereas lab-grown diamonds are created in a few weeks in specialised laboratories. This chemical difference between natural and lab-grown diamonds is limited solely to the formation process, because at the molecular level they are perfectly identical. These identical properties explain why it is impossible to tell a lab-grown diamond from a natural one with the naked eye: only specialised instruments can reveal their different origins.

How lab-grown diamonds are made

There are currently two main methods for creating lab-grown diamonds. Each takes a different approach to reproducing the natural conditions in which diamonds form, yielding stones with specific characteristics.

Properties and characteristics of lab-grown diamonds

Lab-grown diamonds have all the remarkable properties that natural diamonds are famous for:

Physical properties

• Exceptional hardness: 10 on the Mohs scale, maximum scratch resistance
• Unrivalled brilliance: A refractive index of 2.42 that creates a unique sparkle
• Thermal conductivity: Excellent conductivity, higher than that of copper
• Chemical stability: Exceptional resistance to corrosion and acids

Optical properties

• Light dispersion: The ability to split white light into a rainbow
• Fluorescence: Possible reaction under UV light depending on the production method
• Transparency: Perfect light transmission in the higher grades

These remarkable properties mean that lab-grown diamonds have traditionally been graded on the same criteria as natural diamonds: the famous 4Cs (Carat, Cut, Colour, Clarity). However, one recent development is worth highlighting: the GIA (Gemological Institute of America) has recently adapted its grading criteria because lab-grown diamonds are often of exceptional quality, sometimes better than natural diamonds. Indeed, lab-grown diamonds can reach levels of purity and crystal perfection rarely found in nature, which called for a revision of grading standards. Nevertheless, most other certification laboratories continue to apply the same grading criteria to both types of diamond.

Differences between natural and lab-grown diamonds

Although chemically and physically identical, natural and lab-grown diamonds differ in several respects:

Differences in origin and formation

• Formation time: Millions of years for natural diamonds versus a few weeks for lab-grown ones
• Formation conditions: Natural geological process versus a controlled laboratory environment
• Environmental impact: Intensive mining versus laboratory production with a controlled footprint
• Social aspects: Risks linked to working conditions in mining versus skilled technology jobs
• Traceability: Origin sometimes hard to establish versus full traceability of production

Detectable technical differences

• Specific inclusions: Natural diamonds contain unique geological inclusions, while lab-grown diamonds may show traces linked to their production method
• Growth patterns: A slightly different crystal structure, visible under a specialist microscope
• Fluorescence response: Some lab-grown diamonds behave distinctively under UV light (though not all)
• Spectroscopic analysis: A different molecular signature, detectable only with advanced scientific equipment

Differences in perception and impact

When it comes to lab-grown versus natural diamond prices, lab-grown diamonds generally cost 30 to 50% less, which often raises the question: do lab-grown diamonds lose value? For diamonds under 3 carats and classic white diamonds, whether natural or lab-grown, the question of financial investment generally does not arise. Gold remains the true investment asset in jewellery.

From an ethical point of view, ethical and eco-friendly lab-grown diamonds offer significant advantages. These stones eliminate concerns about “conflict diamonds” and significantly reduce environmental and social impact. The environmental impact of lab-grown diamonds is considerably lower than that of traditional mining, although production remains energy-intensive.

It is crucial to understand that lab-grown diamonds are real diamonds in their own right, not imitations. This distinction is fundamental to knowing how to recognise a real lab-grown diamond: unlike substitutes such as cubic zirconia, moissanite or glass, which try to reproduce the look of diamond with different materials, lab-grown diamonds have exactly the same chemical composition and the same crystal structure as natural diamonds. To tell real diamonds from fakes, professionals rely on precise criteria: hardness, thermal conductivity, refractive index and molecular structure. On every one of these points, lab-grown diamonds fully meet the characteristics of a “real” diamond. The only difference lies in how they form: one in high-tech laboratories, the other deep within the Earth.

Coloured diamonds: the colour revolution

One of the most fascinating aspects of lab-grown diamonds is their ability to reproduce, and even surpass, nature when it comes to colour. While natural coloured diamonds are among the rarest and most expensive stones in the world, lab growth opens up an unprecedented world of colour and makes these colourful wonders far more accessible.

The exceptional rarity of natural coloured diamonds

In nature, coloured diamonds are extraordinarily rare. Gem-quality natural pink diamonds account for just 0.01% of global production, and natural green diamonds are rarer still. These colours result from very specific geological anomalies: chemical impurities, exposure to natural radioactivity, or particular crystal deformations that occurred during their formation over millions of years.

This extreme rarity explains why natural coloured diamonds fetch astronomical prices at auction. In 2017, the 59.60-carat “Pink Star” pink diamond sold for $71.2 million, setting a world record.

Technological mastery of lab-grown colours

Lab-grown diamonds are changing the game by making it possible to create colours in a controlled and reproducible way. Scientists can now “programme” a diamond's colour by adding specific elements during the growth process:

The full palette of available colours

• Pink diamonds: Obtained through a specific heat treatment or particular growth conditions. These stones offer all the romance and elegance of natural pink diamonds, perfect for designs such as the Loop ring with a pink pear diamond. Discover all the secrets of these exceptional stones in our guide to the magic of pink diamonds

• Green diamonds: Created by controlled exposure to certain types of radiation or by incorporating specific impurities. This colour, exceptionally rare in nature, becomes accessible thanks to lab growth. Our article on the rarity of green diamonds explores this fascinating colour in detail
• Blue diamonds: Produced by incorporating boron into the crystal structure. These diamonds faithfully reproduce the beauty of legendary natural blue diamonds such as the Hope Diamond
• Yellow diamonds: Created by the controlled addition of nitrogen during growth. From pale yellow to intense canary yellow, a whole range of shades becomes possible
• Orange, champagne and cognac diamonds: Obtained through various combinations of impurities and treatments, offering warm, sophisticated hues

The revolutionary advantages of lab-grown coloured diamonds

Affordability

The main advantage of lab-grown coloured diamonds is their price. Whereas a 1-carat natural pink diamond can cost between €50,000 and €500,000 depending on its quality, an equivalent lab-grown pink diamond will cost between €3,000 and €15,000. This price difference allows a much wider public to enjoy the beauty of coloured diamonds.

Control over quality and intensity

Lab growth allows precise control over colour intensity. Laboratories can produce diamonds with perfectly saturated, even colours, often more intense than their natural counterparts. This technical mastery guarantees a consistency of quality that is impossible to achieve with natural stones.

Creating matching sets

Thanks to controlled production, it becomes possible to create perfectly matched sets: earrings with diamonds of identical colour and intensity, or necklaces composed of harmonious colour gradations. This was virtually impossible with natural diamonds because of their rarity.

Innovation in contemporary jewellery

Lab-grown coloured diamonds unleash the creativity of contemporary jewellers. They can now design bold pieces that mix several colours, create spectacular colour gradients, or offer bespoke creations featuring the client's favourite colour.

This democratisation also brings coloured diamonds within reach for everyday lab-grown diamond jewellery pieces, such as colourful diamond studs that turn these exceptional stones into affordable pleasures. For those wondering where to buy ethical lab-grown diamonds, specialist lab-grown diamond jewellery brands now offer a wide selection of responsible, traceable designs.

The colourful future of diamonds

Ongoing research into lab-grown diamonds hints at even more extraordinary possibilities. Scientists are exploring new methods to create never-before-seen colours, colour-change effects depending on the lighting, and diamonds with special optical properties.

This colour revolution is redefining the aesthetic codes of modern jewellery, where colour becomes a vehicle for artistic expression, freed from the constraints of natural rarity. Lab-grown coloured diamonds do not merely copy nature: they transcend it, offering designers and lovers of fine stones a new visual language of unrivalled richness.

Detection and identification: technologies and regulations

The growing sophistication of lab-grown diamonds calls for ever more advanced detection methods to determine their origin.

Professional detection methods

Today, professionals use cutting-edge technologies to identify the origin of diamonds:

Advanced analysis techniques

• Photoluminescence spectroscopy: This technique analyses each diamond's unique “light signature” by studying how it reacts to certain wavelengths
• Specialist microscope examination: Observation of internal growth patterns, which differ according to origin
• UV fluorescence tests: Some lab-grown diamonds show characteristic reactions under ultraviolet light
• Infrared spectroscopic analysis: Detection of specific impurities and molecular structures

Stronger certification and traceability

Faced with the growing sophistication of lab-grown diamonds and their perfect resemblance to natural diamonds, the certification industry has had to evolve quickly. The stakes are high: to give consumers clear and reliable identification of their diamond's origin, while maintaining trust across the entire diamond market.

This adaptation proved necessary because traditional diamond grading methods could no longer tell lab-grown stones from natural ones. Certification laboratories therefore developed new protocols, invested in state-of-the-art equipment and trained their gemmologists in the specific features of lab-grown diamonds.

Recognised certification bodies

Today, several leading international bodies offer specialised certification services for lab-grown diamonds:

• GIA (Gemological Institute of America): The world leader in certification, the GIA pioneered the identification of lab-grown diamonds. The institute issues specific reports clearly marked “Laboratory-Grown Diamond” and uses advanced analytical techniques to determine origin and production method
• IGI (International Gemological Institute): An international certification body recognised in more than 18 countries, the IGI has developed strict protocols for identifying lab-grown diamonds. Its reports explicitly state the lab-grown origin and include detailed information about the production method
• HRD Antwerp: A leading European centre for diamond certification, HRD Antwerp provides specialised grading reports for lab-grown diamonds, ensuring their precise identification according to European standards
• SCS-007 standard: A specific international standard developed for lab-grown diamonds, it guarantees not only traceability and quality but also transparency in production processes and verification of ethical production conditions

Advanced traceability technologies

Beyond certification alone, lab-grown diamonds now benefit from exceptional traceability. Unlike natural diamonds, whose origin can sometimes be hard to establish, every lab-grown diamond can be tracked from its creation to its final sale.

This traceability includes precise data on the production method used, the manufacturing conditions, the date of creation, and sometimes even a microscopic laser inscription invisible to the naked eye but detectable by professionals. Some producers go as far as offering a “digital passport” for each diamond, accessible via QR code and containing the stone's entire history.

International regulation: ensuring market transparency

With the rise of lab-grown diamonds, authorities around the world quickly understood the importance of putting strict regulatory frameworks in place. These regulations aim to protect consumers by guaranteeing clear and transparent information about the origin of diamonds, while preserving trust in the global diamond market.

French regulation

In France, the law requires clear identification, with the mandatory use of the terms “diamant de synthèse” or “diamant synthétique” (synthetic diamond) in any sale or commercial presentation. This obligation applies to all jewellery professionals, from retail to public auctions.

International standards

The legislation on buying lab-grown diamonds varies from country to country:

• United States: Since 2018, the FTC (Federal Trade Commission) has allowed the term “diamond” to be used for lab-grown stones, provided their origin is clearly identified. Sellers must use qualifiers such as “laboratory-grown”, “laboratory-created” or “synthetic”
• European Union: A European directive requiring the synthetic origin to be stated in all commercial communications, ensuring transparency for European consumers
• Germany: Particularly strict regulation, with tighter labelling checks and significant penalties for non-compliance
• ISO 18323 standard: An international standard defining identification and naming criteria, serving as a global reference for the industry

Conclusion

Lab-grown diamonds represent a major technological revolution that is redefining the codes of modern jewellery. By offering stones that are chemically and physically identical to natural diamonds, yet produced ethically and sustainably, they meet the expectations of a new generation of consumers who are aware of social and environmental issues.

Whether for creating exceptional jewellery or exploring new colour palettes, lab-grown diamonds open up unprecedented possibilities. The fact that they can be produced to precise specifications, their full traceability and their more accessible price make them a credible and attractive alternative.

This transformation echoes the evolution of other luxury sectors that have undergone similar revolutions. The pearl industry illustrates this dynamic perfectly with the arrival of Mikimoto cultured pearls in the early 20th century. Initially rejected by purists, cultured pearls eventually dominated the market, relegating natural pearls to the status of rare curiosities. Likewise, the fur industry has seen synthetic and alternative materials radically transform consumer habits, driven by ethical and environmental considerations similar to those behind the adoption of lab-grown diamonds.

Today, the market is organised around two distinct segments that coexist harmoniously. On one side, exceptional diamonds (large natural stones of outstanding quality) keep their aura of rarity and their investment potential. On the other, in everyday fine jewellery, lab-grown diamonds are rapidly gaining ground thanks to their attractive value for money. This split is redefining business strategies: high jewellery houses are holding their position on exceptional natural stones, while mass-market jewellers are integrating lab-grown diamonds into their collections on a large scale.

For the care of your diamonds, whether natural or lab-grown, the same precautions apply to preserve their exceptional brilliance over time. Lab-grown diamond care and cleaning follows exactly the same protocols as for natural diamonds: regular cleaning with soapy water, and avoiding knocks and harsh chemicals. The future of the diamond industry is thus taking shape around a structured coexistence: exceptional stones (rare natural diamonds of large size and outstanding quality) will keep their status as unique geological treasures, while jewellery stones (diamonds intended for everyday jewellery and accessible designs) will see growing adoption of lab-grown diamonds, enriching the fascinating world of gemstones.