Lab-grown diamonds are real diamonds created in a controlled laboratory environment, with the same chemical and optical properties as mined diamonds. This guide is informed by Hamish Whiting, Cushla Whiting founder, GIA Gemologist and HRD Antwerp Diamond Grader, who buys diamonds in Antwerp and selects stones with a focus on cut, proportion and long-term performance.
How lab-grown diamonds are made
What are lab-grown diamonds? They begin with a small diamond seed, placed in conditions that allow carbon atoms to form around it in a diamond crystal structure. The two main methods are HPHT and CVD.
HPHT stands for High Pressure High Temperature. It recreates the pressure and heat conditions under which diamonds form naturally underground. Meanwhile, CVD stands for Chemical Vapour Deposition. It uses a carbon-rich gas in a chamber, allowing carbon to build gradually on the diamond seed.
Both methods can produce real diamonds. The difference is how the crystal grows, and what may need to happen after growth to improve the stone's colour or appearance.
| Method | How it works | What to know |
|---|---|---|
| HPHT | Uses high pressure and high temperature to grow a diamond from a seed. | Can create high-quality diamonds, though some stones may show metallic inclusions. |
| CVD | Uses carbon-rich gas to build diamond crystal layer by layer. | Common in the market; some stones may receive post-growth treatment to improve colour. |
1. They are real diamonds, but real and rare are different things
A lab-grown diamond has the same carbon lattice as a natural diamond and rates 10 on the Mohs hardness scale. It is not a simulant, and it is not cubic zirconia or moissanite.
The important distinction is rarity. Natural diamonds formed over billions of years and exist in finite supply. Lab-grown stones can be manufactured to demand. The material is the same, but the scarcity story is not.
2. Ask which method grew the stone
When comparing lab diamonds in Australia, ask whether the stone was grown by HPHT or CVD. This is not about one method being universally better than the other. It is about transparency.
HPHT stones can carry metallic inclusions. CVD stones may need post-growth treatment to improve colour. A reputable retailer should be able to tell you the growth method, whether treatment is noted, and how the stone was assessed. If they cannot answer clearly, that is useful information.
3. Lab-grown grading is not natural diamond grading
Certification matters, but lab-grown diamond grading is not identical to natural diamond grading. Most lab-created diamond rings on the market are graded by IGI. GIA uses a different report format for laboratory-grown diamonds, with a quality assessment that distinguishes them clearly from natural stones. HRD Antwerp no longer grades loose lab-grown diamonds.
This does not mean certification is unimportant. It means you should understand which laboratory issued the report, what the report includes and whether it confirms the manufacturing technique, measurements, colour, clarity, cut and any relevant comments.
4. Price is the point — just understand what drives it
The price advantage of lab-grown diamonds comes from supply. They are manufactured, which means availability can grow quickly and production costs can fall over time.
That makes lab-grown a practical choice if you want a larger stone or higher specifications for the same budget. It also means resale should not be the reason you buy one. We recommend choosing lab-grown for affordability, size, and personal preference, not because you expect it to hold value like a rare natural or antique diamond.
5. Do not buy on carat weight alone
One of the biggest advantages of lab-grown diamonds is that your budget can go further — but that doesn't necessarily mean you should choose the largest diamond you can afford. The emergence of lab-grown diamonds has led to an explosion of 4–5 carat plus rings on social media, but we recommend trying this size on before committing to it.
6. Cut quality still separates good stones from ordinary ones
Because lab-grown material is more available, cut is where the real difference lives. A poorly cut lab-grown diamond can look dull, even with a high colour and clarity grade. In contrast, a well-cut stone will return light more effectively and appear brighter on the hand.
This is also why Cushla Whiting assesses proportion, symmetry and light performance rather than relying on the certificate alone. Our exclusive La Cush™ diamond cut is one example of how cut can shape the character and performance of a diamond.
7. Lab-grown does not automatically mean more ethical
Lab-grown diamonds avoid mining, but they are still energy-intensive to produce. The ethical picture depends on the producer, the energy source and the transparency of the supply chain.
Natural and antique diamonds have their own considerations, too. Antique diamonds are already in circulation, while modern natural diamonds depend heavily on the quality and visibility of the sourcing chain. For a deeper comparison, read our guide to lab-grown, natural and antique diamonds.
8. See it in person, in natural light
Jewellery shop lighting is designed to flatter diamonds and hide imperfections. View the stone in natural diffused light where possible.
If you are choosing between modern cut, antique and lab-grown diamonds, seeing them together is often the clearest way to understand the difference. For natural diamonds versus lab diamonds, the clearest way to understand the difference is to look at the value of each. Book a Melbourne, Sydney or virtual appointment to compare stones with a diamond specialist.
Natural, antique and lab-grown compared
| Comparison | Natural (modern cut) | Antique | Lab-grown |
|---|---|---|---|
| How it formed | In the earth over billions of years | In the earth over billions of years | Grown in weeks via HPHT or CVD |
| When it was cut | Cut today, modern proportions | Hand-cut, typically pre-1930s | Cut today, modern proportions |
| How it looks | Precise, uniform, maximum brilliance | Softer and warmer, larger flashes of light, small irregularities from hand-cutting | Same optical properties as natural — brilliance comes from the cut, not the origin |
| Availability | Finite; large high-grade stones are rare and expensive | Genuinely finite — no more are being made | Produced to demand, in growing volumes |
| Certification | Full 4Cs from GIA, HRD and other major labs | Often uncertified, or graded to modern standards not designed for old cuts | Usually IGI. GIA grades to a simplified descriptor, not full 4Cs. HRD does not grade them |
| Relative price | Higher | Varies — scarcity sets it, not age | Very affordable |
| Value over time | Underpinned by finite supply | Underpinned by finite supply and rarity of cut | Production costs have fallen; resale is not a reason to buy |
| Ethical picture | Kimberley Process, plus direct sourcing where the chain is visible | Already in circulation — no new extraction | No mining, but growth is energy-intensive and the energy source varies by producer |
| Suits someone who | Wants a certified stone with precise, contemporary brilliance | Wants character, and a stone that cannot be replicated | Wants size or specification at a lower price point |
FAQs
What are the main differences between lab-grown and natural diamonds?
The main differences are origin, rarity and long-term value. Lab-grown diamonds are created in controlled laboratory conditions, while natural diamonds form underground over billions of years. They share the same chemical and optical properties, but natural diamonds are finite, while lab-grown diamonds can be produced to demand.
Are lab-grown diamonds cheaper?
Yes, lab-grown diamonds cost a lot less than natural diamonds because they can be manufactured at scale. This makes higher specifications or larger stones more accessible.
Are lab-grown diamonds more ethical?
Not automatically. Lab-grown diamonds avoid mining, but production is energy-intensive, and the ethical picture depends on the producer, energy source and transparency of the supply chain. Natural diamond mining provides jobs and opportunities to the communities and nations where the mines are located, often in developing nations. Antique diamonds have different considerations, so it is worth comparing all three before deciding.
Are lab-grown diamonds as hard as natural diamonds?
Yes. Lab-grown diamonds and natural diamonds are both made from carbon arranged in a diamond crystal structure, and both rate 10 on the Mohs hardness scale. This means they offer the same resistance to scratching and are suitable for jewellery designed for long-term wear.
Will lab-grown diamonds test real?
Lab-created diamond rings may test as diamonds on basic diamond testers because they have the same chemical composition as natural diamonds. However, specialised testing equipment can identify lab-grown origin through growth patterns, inclusions or laser inscriptions that are not visible to the naked eye.
Can jewellers tell the difference between diamonds and lab-created diamonds?
Not by sight alone in most cases. A well-cut lab-grown diamond can look the same as a natural diamond to the eye. Gemologists use specialised tools, magnification and testing equipment to identify growth characteristics, inclusions or inscriptions that indicate laboratory-grown origin.
Speak to a diamond specialist
Choosing between natural, antique and lab-grown is easier when you can compare stones properly. Cushla Whiting offers appointments in Melbourne, Sydney and virtually, giving you access to expert guidance from a team that understands cut, quality, proportion and value. If you are considering lab-created diamond engagement rings, speak to a diamond specialist before you choose.
