Complete Lab-Grown Diamond Guide
Lab-grown diamonds are chemically, physically, and optically identical to mined diamonds. This guide covers how they are made, how they are graded, what they cost, and how to decide if they are right for you.
What Are Lab-Grown Diamonds
Lab-grown diamonds are real diamonds created in controlled laboratory environments rather than mined from the earth. The FTC confirmed in 2018 that they are genuine diamonds.
- Same chemical composition as mined diamonds — pure carbon arranged in a cubic crystal structure.
- Same hardness (10 on the Mohs scale), same brilliance, same fire. Even gemologists cannot tell them apart without specialised equipment.
- Graded by the same laboratories (GIA, IGI) using the same 4Cs standards as mined diamonds.
- Not to be confused with diamond simulants like cubic zirconia or moissanite, which are different materials entirely.
- Growing in popularity — over half of engagement ring buyers now consider lab-grown diamonds.
The Simple Truth
A lab-grown diamond and a mined diamond of the same grade look identical, perform identically, and are graded identically. The only difference is origin.
Why People Choose Them
Most buyers choose lab-grown diamonds because they can get a larger or higher-quality stone for the same budget, with a clearer sourcing story.
How Lab-Grown Diamonds Are Made
Two methods replicate natural diamond formation. Both produce genuine diamonds with the same crystal structure and properties.
HPHT — High Pressure High Temperature
Mimics the conditions deep within the earth. A small diamond seed is placed in carbon material and exposed to extreme pressure (around 1.5 million pounds per square inch) and temperatures above 1,400°C. The carbon melts and crystallises around the seed over days to weeks.
CVD — Chemical Vapor Deposition
A diamond seed is placed in a sealed chamber filled with carbon-rich gas (usually methane). The gas is heated to around 800°C, breaking down the carbon atoms which then deposit onto the seed layer by layer. This method produces diamonds in weeks to months.
The 4Cs for Lab-Grown Diamonds
Lab-grown diamonds are graded using the same 4Cs system as mined diamonds. Here is what to prioritise when choosing yours.
CUT
The most important factor for brilliance. A well-cut lab-grown diamond will outperform a larger stone with weaker light return. Prioritise cut quality above all else.
COLOUR
Lab-grown diamonds are available across the full D–Z colour range. G–H grades offer excellent value — nearly colourless at a lower cost than D–F. Read more in our diamond colour chart guide.
CLARITY
Lab-grown diamonds can achieve higher clarity grades more consistently than mined stones. VS2 to SI1 offers the best value for most engagement rings. See our diamond clarity chart guide for details.
CARAT
Because lab-grown diamonds cost less per carat, you can often move up in size without exceeding your budget. A 2-carat lab-grown diamond can cost less than a 1-carat mined stone of equivalent quality.
Value & Worth
Lab-grown diamonds cost significantly less than mined diamonds of the same quality. But the value question is more nuanced than price alone.
- Lab-grown diamonds typically cost 50–70% less than equivalent mined diamonds.
- The price advantage lets you prioritise a better cut, a larger stone, or a more refined setting.
- Resale value is low — lab-grown diamond prices have dropped as production has scaled. If resale matters to you, this is worth considering.
- If you plan to keep the ring forever, resale value is less relevant than the quality and beauty of what you wear every day.
Good Fit If You
- • Want a larger diamond for your budget
- • Plan to keep the ring forever
- • Value what the diamond represents over its origin
- • Prefer a clearer sourcing story
Less Suited If You
- • Might sell or trade the stone later
- • Value natural rarity and formation
- • Want established resale markets
Lab-Grown vs Natural Diamonds
Both are real diamonds. The differences come down to origin, price, value retention, and environmental impact.
| Factor | Lab-Grown | Natural |
|---|---|---|
| Composition | Pure carbon | Pure carbon |
| Hardness | 10 (Mohs) | 10 (Mohs) |
| Price | 50–70% less | Premium |
| Resale Value | Low | Moderate |
| Environmental Impact | Lower footprint | Mining impact |
| Certification | GIA / IGI | GIA / IGI |
Lab-Grown Diamonds vs Moissanite
Both are excellent choices for engagement rings, but they are different materials with different properties.
- Lab-grown diamonds are pure carbon with a hardness of 10. Moissanite is silicon carbide with a hardness of 9.25.
- Moissanite has more fire (rainbow flashes) than diamond. Diamond has a more traditional white sparkle.
- Moissanite costs 80–90% less than equivalent lab-grown diamonds, making it the best option for maximising size on a budget.
- Both are lab-created and ethically sourced. Both are durable enough for daily wear.
Choose Lab-Grown Diamond If
- • You want a true diamond
- • Traditional white sparkle matters
- • You want GIA/IGI certification
Choose Moissanite If
- • You want maximum brilliance and fire
- • Budget is a key factor
- • You prefer a larger stone
Care & Maintenance
Lab-grown diamonds are as durable as mined diamonds and require the same simple care.
Cleaning & Storage
- Clean with warm water, mild soap, and a soft brush
- Store separately to prevent scratching other jewellery
- Ultrasonic and steam cleaners are safe for diamonds
- Have settings inspected annually to ensure prongs are secure
Explore Lab-Grown Diamond Jewellery
Browse our collection of lab-grown diamond engagement rings, or explore the custom design process to build something tailored to your brief.