Two diamonds. One pulled from the ground, one grown in a reactor. Under a 10x loupe an IGI gemologist cannot tell them apart — because they are the same crystal. Same atomic lattice, same Mohs 10 hardness, same 2.42 refractive index. The only real differences are origin, footprint and price.
Key takeaways
- Lab-grown and mined diamonds are physically, chemically and optically identical — both are real diamonds.
- They are graded by the same laboratories (IGI, GIA) on the same 4Cs.
- The differences are origin, environmental footprint and price — not the stone itself.
- A lab-grown stone of identical specs typically costs 60–80% less than mined at retail.
- How a diamond looks is decided by cut, not origin.
What is identical
Lab-grown diamonds are physically, chemically and optically the same as mined diamonds: carbon in a cubic crystal structure, the same fire, the same brilliance, the same hardness. They are graded by the same labs on the same 4Cs scale — if those are new to you, see the 4Cs explained.
What is different
The origin story. A mined diamond grew over billions of years a hundred miles below the surface and was carried up by volcanic activity. A lab-grown diamond grows over weeks in a reactor that recreates those conditions — the same temperature, pressure and chemistry. Both processes produce diamond. One leaves a roughly 250-ton-per-carat earth disturbance behind it; the other, a few kilowatt-hours.
Lab-grown vs mined, side by side
| Property | Lab-grown | Mined |
|---|---|---|
| Chemical / optical make-up | Identical (real diamond) | Identical (real diamond) |
| Hardness | Mohs 10 | Mohs 10 |
| Certification | IGI / GIA, same 4Cs | IGI / GIA, same 4Cs |
| Origin | Grown in weeks | Formed over billions of years |
| Environmental footprint | Minimal | Significant extraction |
| Price (same specs) | 60–80% less | Baseline |
What actually matters for your ring
Cut. Then cut. Then cut. A 3-carat VVS1 D-colour stone with a mediocre cut will look duller than a smaller stone cut to Triple Excellent. We set Montare's floor at Triple Excellent for that exact reason — it is the variable that separates a diamond that catches every angle of light from one that just sits there. Here is why Triple Excellent matters.
The pricing question
A lab-grown stone of identical specifications costs 60–80% less at retail than its mined counterpart — and that is before retail markup. The difference is not a discount on quality; the stone is identical. It is the absence of a century-old extraction industry and the layers of markup on top of it. We run the numbers in what an $11,000 lab-grown ring is really charging you for, and cover the Canadian specifics in our guide to buying lab-grown in Canada.
What we will not say
We will not tell you lab-grown is ‘better’ than mined — they are the same crystal. We will tell you that at the VVS, D/E, Triple Excellent floor Montare insists on, the value calculation is straightforward: you are paying for the stone, the craftsmanship and the standard, not for an extraction story.
Frequently asked questions
Are lab-grown diamonds real diamonds?
Yes. A lab-grown diamond is a real diamond — identical carbon crystal, hardness and brilliance — simply grown in a lab rather than mined. It is not a simulant like cubic zirconia or moissanite.
Can a jeweller tell lab-grown from mined?
Not by eye or with a loupe — they are identical. Distinguishing them requires specialised laboratory equipment, which is why the certificate states the origin.
Do lab-grown diamonds hold their value?
Like most diamonds, lab-grown stones are not bought as investments — choose the ring you love, not a stone to resell. The value is in buying a far larger, higher-grade diamond for the same budget.
Why are lab-grown diamonds cheaper?
Because the supply chain is shorter and there is no extraction industry behind them — not because the stone is lesser. Same diamond, less arithmetic between you and it.
See the standard for yourself. Build a ring in the ring builder or book a consultation.