How lab grown diamonds are made and 5 reasons you should choose them over natural diamonds

Diamonds may be a girl’s best friend, but they’re far from friendly on the wallet. Thankfully, lab-grown diamonds offer more sparkle for your buck.

They are almost identical to natural diamonds and come in different colours, carat weights and shapes, making them a great choice if you want a bigger stone for a ring or watch for a lower price tag.

How lab-grown diamonds are made

Lab diamonds have essentially the same chemical and physical composition as their natural counterparts, unlike cubic zirconias or any other sparkly alternatives.  To the naked eye, lab diamonds are identical to nature’s bling, although they can be distinguished by specialist kit. The big difference – aside from rarity and value – is the process used to make them.

Natural diamonds form in the Earth’s mantle when the right amount of heat and pressure bond carbon atoms together. These gemstones are stunning and limited in quantity making them super valuable – supply and demand baby! – helped by a very successful advertising campaign by De Beers in the 1940s. You know the one – ‘A diamond is forever’.

Unlike natural diamonds, lab diamonds don’t take almost forever to form. Instead, they can be ‘grown’ in a couple of weeks.

Lab diamonds, as you might have guessed, are made in a laboratory using one of two processes.

The first is High Pressure, High Temperature (HPHT) which mimics the conditions deep in the Earth. Firstly, a tiny diamond ‘seed’ is placed in a specially designed press with carbon (usually graphite) and a metal catalyst that’s heated to 1,300–1,600°C and put under incredible pressure. The molten metal dissolves the high purity carbon source, and the carbon atoms precipitate on a small diamond seed crystal. Then, the diamond grows before being cut and polished by an expert.

The second method – Chemical Vapor Deposition (CVD) – conjures diamonds from gas. To be more specific, it involves filling a vacuum chamber with carbon-containing gas that is heated to about 900-1200°C. A microwave beam causes carbon to precipitate out of a plasma cloud and deposit onto a seed crystal. Diamonds are removed every few days to have the top surface polished to remove any non-diamond carbon. It takes three or four weeks to ‘grow’ a stone and scientists have the ability to tweak the process to change a diamond’s colour, for example.

Despite these mind-boggling processes, lab grown diamonds have caught on bigtime. An estimated 6–7 million carats of synthetic diamonds were created in 2020, according to a report and the market (plus diamonds) have continued to grow. So why choose them?

1. Same sparkle for less cash

Lab-grown diamonds look just as good, boasting similar physical, chemical, and optical properties to their mined counterparts. They are generally much less expensive than comparable natural diamonds – as much as 75% less – but this difference varies by size, quality and retailer. The price difference allows buyers to declare their love in a bigger way by sizing up the stone for a ring, or by saving some money without compromising sparkle or sentiment.

2. Traceable, conflict-free supply chains

Diamond mining has a history of being unethical and harmful to the environment. You might have seen the film Blood Diamond with Leonardo DiCaprio to give you a flavour. From poor working conditions and the use of child labour to diamond mine earnings being used to fund wars, diamond mining can be fraught with humanitarian and ethical issues.

While it’s possible to buy ethical diamonds with good provenance and choose second-hand gems to minimise the prospect of doing harm, lab diamonds should be easier to trace, although you should still scrutinise a company’s business practices and whether they use renewable energy, if doing as little harm as possible to people and the environment is important to you.

3. Better for the environment

To say that diamond mining is not good for the environment is a bit of an understatement. Traditional diamond mining relies on heavy machinery, explosives, and hydraulic equipment to extract diamonds. The process that yields a staggering 57,000 grams of greenhouse gas (GHG) emissions, produces 2.63 tonnes of mineral waste, and consumes 0.48 m³ of water per carat, according to figures from 2014 incorporated in a 2024 study. Now consider that in 2019, the global diamond industry produced almost 136 million carats of diamonds and demand has increased since. That’s a lot of damage to planet Earth, even if figures vary by mine.

In contrast, the rise of lab-grown diamonds represents a vital shift towards environmental sustainability, because they can be produced at a fraction of the environmental cost. If clean energy sources are used to grow diamonds, just 0.028 grams of GHG emissions, 0.0006 tonnes of mineral waste, and 0.07 m³ of water is used per carat, according to the study. That means, the ice on your finger doesn’t have to negatively impact the ice at the Poles.

4. More colour options

Celebrities love rare, colourful diamonds. Mariah Carey reportedly has a massive pink diamond at the heart of her engagement ring, while Kelly Clarkson has canary yellow bling. Jennifer Lopez’s engagement ring from Ben Affleck has a rare green diamond (and she’s previously worn pink and blue diamonds). She may still be Jenny from the block and used to have a little, but now she certainly has some fabulous rings.

While eye-wateringly expensive coloured diamonds created by mother nature are great for A-listers attending The Oscars, us mere mortals can have a more accessible slice of the sparkly rainbow thanks to lab-grown diamonds. This is because growers can create fancy colours by adding specific trace elements or gases to diamond seeds, imitating the geological conditions that make coloured diamonds naturally.

For example, yellow diamonds get their colour from nitrogen trace elements. So, scientists can add nitrogen trace elements to lab-grown diamonds, with small amounts creating light yellow gems, and large amounts canary yellow diamonds. Blue diamonds like the famous Hope Diamond form deeper under the Earth’s surface than other diamonds, and get their colour from an element called boron. So, adding small amounts of boron in the lab yields pale blue diamonds, with deeper blues created by adding more – although the diamond’s structure and the way impurities occur matter too.

Intriguingly, natural pink diamonds look pink due to their unique crystal structure created by intense volcanic heat and pressure. They can be recreated in the lab through particular growth or treatment processes, including heating, pressure and irradiation.

5. Flexibility and availability

As well as being able to create colourful gemstones, scientists can influence the ‘4 Cs’ – colour, clarity, cut and carat weight – in the lab. As supply isn’t dictated by Mother Nature and geology, they can theoretically create whatever sizes they like in as large a quantity as they want, although obviously time, resources and money are factors. So, gem-encrusted tiaras and large, intricate necklaces, like Audrey Hepburn wears in Breakfast at Tiffany’s can more easily be made from lab-grown diamonds.