Lab-Grown Diamonds
Lab-grown diamonds, explained.
Lab-grown diamonds have transformed fine jewellery. They have the same essential chemical composition, crystal structure, hardness and optical properties as mined diamonds, with a clearly disclosed laboratory-grown origin and no new diamond mining. Here is what is actually true, and what is not.
They are real diamonds
A lab-grown diamond has the same essential chemical composition, crystal structure, hardness and optical properties as a mined diamond. Both are crystallised carbon and look the same to the naked eye. Specialist laboratories can identify growth origin using advanced instruments and can independently assess quality.
The US Federal Trade Commission updated its Jewelry Guides in 2018 to recognise laboratory-grown stones within its definition of diamond, provided their origin is clearly disclosed. IGI issues detailed 4Cs grading reports for lab-grown diamonds, documenting their laboratory-grown origin and key quality characteristics.
They are not simulants, not imitations, and fundamentally different from cubic zirconia or moissanite, which are different materials entirely.
Lab-grown vs mined — side by side
| Lab-grown diamond | Mined diamond | |
|---|---|---|
| Chemical composition | Pure carbon (C) | Pure carbon (C) |
| Hardness (Mohs scale) | 10 — hardest known material | 10 — hardest known material |
| Refractive index | 2.42 | 2.42 |
| Sparkle and fire | Equivalent optical performance at the same cut quality | Equivalent optical performance at the same cut quality |
| Certification | IGI 4Cs grading report | Independent 4Cs grading report |
| Origin | Controlled laboratory, weeks to months | Underground formation over millions of years |
| Supply chain | Laboratory-grown origin disclosed; producer traceability varies | Transparency varies |
| Value for your budget | Exceptional — a finer, larger or more ambitious piece for the same outlay | Pricing carries a long, traditional supply chain |
| Visible difference | No reliable visible difference. Specialist equipment can identify growth origin. | |
How they're made
Two methods produce gem-quality lab-grown diamonds:
HPHT — High Pressure High Temperature
The older of the two methods. A small diamond seed is placed into a carbon source and subjected to the same extreme pressure and temperature that creates diamonds geologically — pressures of around 5–6 GPa at temperatures above 1,300°C. Carbon atoms attach to the seed, growing the crystal layer by layer.
CVD — Chemical Vapour Deposition
A diamond seed is placed in a sealed chamber filled with carbon-rich gas (typically methane and hydrogen). The gas is energised into a plasma, and carbon atoms layer onto the seed, growing the diamond crystal upward. CVD is the more commonly used method for high-quality, larger gemstones because it allows precise control over the growth environment.
Both methods produce a single crystal of pure carbon, structurally indistinguishable from a mined diamond. The end product is the same — only the timescale and the location of growth differ.
The 4Cs still apply
Lab-grown diamonds are graded against exactly the same standards as mined diamonds:
- Cut: the precision and proportions of the diamond's facets — the single most important factor in how a diamond sparkles. A well-cut diamond returns more light than a poorly-cut one of higher carat.
- Colour: graded D (colourless) through to Z (light yellow). We set D–F stones — the colourless end of the scale.
- Clarity: the presence of any internal inclusions or surface blemishes. Graded from Flawless (FL) to Included (I3). Ours are VS1 clarity or better.
- Carat: the weight of the stone. One carat equals 0.2 grams.
Cut and finish determine how a diamond returns light. Round brilliant diamonds can receive a formal cut grade; fancy shapes are assessed through their proportions, polish, symmetry and overall make. We select each stone for strong visual performance. If you would like to talk through which size and shape suits a particular piece, just ask.
Where the value comes from
A lab-grown diamond and a mined diamond of the same specification are the same stone in every way that matters — same cut, colour, clarity and carat, the same brilliance, the same hardness. The difference sits entirely in the journey the stone takes to reach you. A lab-grown diamond is created in a controlled facility and moves directly to the workshop, without the lengthy mining, sorting, trading and traditional retail layers that a mined stone passes through — each of which adds its own cost along the way.
What that means for you is simple: your budget goes further. The same investment can mean a larger stone, a finer cut, a more intricate setting, or a more ambitious design than you might expect. This isn't a compromise and it isn't a lesser product — it's the same diamond, reaching you through a shorter, more transparent route. Every piece we make is priced on the quality of the stones we set and the craftsmanship that goes into it.
Sourcing and traceability
Here, honesty matters more to us than marketing. Our diamonds are grown in a controlled facility rather than mined. The supply chain is traceable from the growing facility through to your finished piece, and every stone is set into a piece made to order rather than mass-produced.
What we won't do is put an environmental comparison in front of you. Growing a diamond uses energy, and the headline figures quoted elsewhere come from studies funded by one side of the industry or the other, and they contradict each other. We'd rather tell you what is verifiable — grown not mined, traceable, made to order — than repeat a claim we can't stand behind. It's the same approach we take to our pricing.
Common myths, answered
"Lab-grown diamonds are fake."
They are not. They are real diamonds, identical in chemical and physical composition to mined diamonds. The US Federal Trade Commission recognises laboratory-grown stones within its definition of diamond when their origin is clearly disclosed, and IGI issues grading reports identifying them as laboratory-grown diamonds.
"Lab-grown diamonds will fade or discolour."
They will not. They have the same hardness (Mohs 10) and the same optical properties as mined diamonds. They will not cloud, scratch easily, or lose their fire with age. They will outlast almost any other gemstone you could choose.
"You can spot the difference."
You cannot. Distinguishing a lab-grown diamond from a mined diamond requires specialist gemological equipment that examines trace elements at the atomic level. To the naked eye, under a loupe, or under standard testing, they look identical because they are identical.
"Lab-grown diamonds won't hold their value."
This is the most honest area of the conversation. Mined diamonds have historically been positioned as an investment, but in practice the resale market for any diamond is far weaker than retail pricing suggests. We do not sell jewellery as an investment, and we don't believe anyone should. We sell jewellery you'll love to wear, made to a standard that lasts a lifetime.
"Lab-grown is the same as cubic zirconia or moissanite."
It absolutely is not. Cubic zirconia is zirconium dioxide — a different material with different physical properties that scratches and dulls over time. Moissanite is silicon carbide — a different mineral with a different refractive index that produces a distinctly different sparkle (often described as a "rainbow" or "disco ball" effect). Both have their place in jewellery, but they are not diamonds. Every stone we set is a real lab-grown diamond.
Certification
Every piece with a centre stone of 1.00ct or above — in silver or gold — comes with an individual IGI grading report as standard, at no extra cost, and it does not add to your lead time.
If you'd like to discuss a piece, a budget, or which specification suits you best, get in touch. Or visit our Custom Jewellery page to start a commission.