Laboratory-grown or earth-mined: how to choose a diamond

Updated 16 October 2026

Both are diamonds. Both are crystallised carbon with the same hardness, the same refractive index and the same chemistry. Put a laboratory-grown diamond and an earth-mined diamond of the same grades side by side and neither you nor a trained jeweller with a loupe will be able to tell which is which. Telling them apart takes specialist equipment that looks at how the crystal grew.

So the choice is not about how the ring will look. It is about three other things: origin, price and long-term value.

Origin

An earth-mined diamond formed deep in the earth over a very long time and was brought to the surface by volcanic activity, then mined, cut and polished. A laboratory-grown diamond is grown from a small diamond seed, either under high pressure and high temperature (HPHT) or by building up carbon layer by layer from a gas (CVD), then cut and polished in exactly the same way.

Some people want a stone that is millions of years old. Others like knowing exactly where and how their stone was made. Neither view is wrong.

Price

This is where the difference is largest. Laboratory-grown diamonds cost a fraction of earth-mined diamonds of the same size and grades, and the gap has widened over the past few years as production has scaled. In practice, the same budget buys either a larger laboratory-grown stone or a smaller earth-mined one.

Our product pages show both prices for every size, so you can see the trade-off directly rather than guess at it.

Long-term value

No diamond is a reliable investment once it has been bought at retail. That said, earth-mined diamonds have a resale market and tend to hold more of their value. Laboratory-grown prices have fallen and may keep falling, so a laboratory-grown stone should be bought for the pleasure of wearing it, not as a store of value.

What does not change

• Grading. Every stone over 0.30 ct we supply comes with an independent grading report. The cut, colour and clarity standards on our product pages apply to both origins.
• The setting. The ring, the metal, the hallmark and the craftsmanship are identical.
• Presentation. Your piece arrives in the same Audley box with the same paperwork, whichever stone you chose.
• Disclosure. We always tell you exactly which you are buying. The origin is stated on your order, your receipt and your grading report. Most laboratory-grown stones also carry a microscopic inscription on the girdle saying so, visible only under magnification.

How to decide

If size and quality within a fixed budget matter most, a laboratory-grown diamond gives you more of both. If the age and rarity of the stone matter to you, or you want something with an established resale market, choose earth-mined. If you are unsure, book a consultation and we will show you both at the same size and grades.