With their cheaper price tag and supposed sustainability credentials, interest in laboratory-grown diamonds (also called lab-grown diamonds, lab-created diamonds, LGDs and synthetic diamonds) is on the rise.
But what exactly are LGDs? Are they really grown in labs and, more importantly, are they even diamonds? Let us take you through the key differentiators between LGDs and their natural counterparts, which include formation, rarity and sentimental value.
What are lab-grown diamonds and how are they made?
LGDs are diamonds that are mass-produced in factories. They have the same chemical and optical properties as natural diamonds, but they’re created in an artificial environment and not by Mother Nature.
Generally, there are two different methods of producing LGDs. Strap in for a science lesson…
One method of production is High-Pressure, High-Temperature (HPHT), which is popular in the US, China and Singapore. This process attempts to recreate the geological conditions required for natural diamonds to grow deep in the Earth, in a factory using powerful high-pressure presses.
The HPHT method involves combining synthetic diamond powder or graphite powder, a metallic solvent and a synthetic diamond seed in a capsule. The capsule is then subjected to extreme heat, ranging from 2,300-2,900°F, as well as intense pressure. This causes the solvent to dissolve the powder, freeing carbon that then builds onto the diamond seed in crystalized form.
Still with us? OK, the second technique used to produce LGDs is Chemical Vapor Deposition (often shortened to CVD). As the name suggests, this process involves using chemical gases, such as methane, to produce crystals.
For CVD, a piece of synthetic diamond (often in a tab-like shape) is placed in a vacuum chamber. A gas containing hydrogen and carbon is then pumped into the chamber, which in turn is heated using microwave energy. This heat causes the gas to ionize, with carbon atoms separating from it and gathering on the synthetic diamond in layers. This process is repeated over the course of a few weeks to create large gems.
What are the differences between lab-grown and natural diamonds?
In addition to lacking the same geological, mythical and sentimental resonance, LGDs also have scientific differences to natural diamonds, though these aren’t obvious to the untrained eye. These include:
Formation time
Scientific research tells us that stardust from the galaxy accumulated in the core of the Earth when it was formed 4.5 billion years ago. Like something from a fairy-tale, this stardust was the source of carbon that, when bonded under intense heat and pressure hundreds of kilometers deep, crystalized and formed diamonds. The gemstones were then brought nearer to the planet’s surface by powerful volcanic eruptions millions of years ago and became lodged in pipe-like rocks.
The oldest diamonds that have been dated are around 3.5 billion years old, whereas LGDs are made over a period of days or weeks.
Growth structures
At a highly magnified level, gemologists can see the difference in crystal growth structures of LGDs compared with those of natural diamonds.
Natural diamonds typically grow in an octahedral shape (think two pyramids stuck together base-to-base), whereas the crystals in HPHT diamonds grow in a more cube-like shape and those of CVD diamonds are formed in tab-like layers.
Clarity characteristics
Because of their long and rather turbulent journey to the Earth’s surface, natural diamonds often have imperfections and internal features.
These unique features, which could be tiny pieces of mineral from the rock in which they grew, are individual birthmarks and make each natural diamond one-of-a-kind.
Due to their human-controlled production process, LGDs rarely have any unique characteristics –any that do occur are a manufacturing mistake. You might find leftover remnants of the raw materials used in the production method, perhaps.
Rarity and preciousness
Lab-created diamonds can be made on demand in large batches, whereas natural diamonds are a truly rare thing.
The world has a finite reserve of natural diamonds because, first and foremost, their supply comes from nature, and second, because most are buried too deep for humans to recover, despite modern mining technology.
The world’s deepest diamond mine, Jwaneng in Botswana, reaches depths of up to 625 meters, however many diamond deposits sit between 140-200 kilometers underground. Unfortunately for diamond lovers, the volcanic eruptions that took place millions of years ago, surfacing the natural gemstones in existence today, won’t happen again in our lifetime.
Emotional and spiritual value
Natural diamonds aren’t just stunning, they’re legendary. For centuries, these glittering gemstones have been treasured not just for their rarity and beauty, but for the powerful stories they carry.
Across cultures and generations, natural diamonds have symbolized love that lasts a lifetime, unwavering strength, hope, and deep, eternal commitment. Some believe they even protect against evil or help to clear the mind, like a cosmic reset button.
Born billions of years ago in the heart of the Earth, natural diamonds are nature’s pièce de résistance, something that LGDs can’t ever replicate.
What’s the difference when it comes to sustainability?
Wondering how lab-grown and natural diamonds compare in terms of sustainability? Well, claims that lab-grown diamonds are more environmentally friendly or sustainable than natural diamonds aren’t always reliable.
Often, the factories and plants where lab-grown diamonds are manufactured, such as those found in India or China, rely on fossil fuels like coal to operate. In addition, other mined materials like iron, nickel and cobalt are required to make lab-grown diamonds.
In terms of social and environmental responsibility, it’s natural diamond mines that are leading the way. Natural diamond mining can bring huge economic growth to countries and communities, with mining sites creating direct employment and providing medical, housing and schooling services to local people.
In some cases, mining companies support or lead biodiversity projects that aim to protect nearby nature reserves and wildlife, too.
So, the big question: are lab-grown diamonds really diamonds?
LGDs are considered diamond material, yes, but cannot be sold without their origin being disclosed. LGDs can’t be referred to or sold as ‘diamonds’ without the relevant prefix – laboratory-grown, laboratory-created, man-made or synthetic. Transparency is key!
Most polished diamonds over 30 points (approx. 0.3 carat) will come with a grading report issued by an independent institute. This will state whether the gem is natural or lab-grown along with its grading in terms of the 4Cs: cut, color, clarity and carat.
In the US, the leading certification bodies are the Gemological Institute of America (GIA), the American Gem Society (AGS) and De Beers Institute of Diamonds, but you may also see certificates issued by the International Gemological Institute (IGI), especially in the case of lab-grown diamonds.
