The materials
A lab-grown diamondis a diamond.
Not a simulant. Not cubic zirconia. Not a "diamond alternative." A lab-grown diamond is carbon crystallised into the same lattice as a mined diamond — the same material, the same 10 on the Mohs hardness scale, the same fire. A gemologist with a loupe cannot tell them apart.
The only difference is where it grew, and how much it cost to get it out of the ground. Which is exactly the part that shouldn't cost you a year's savings.
The process
How one is actually made.
Two methods dominate. Both start with a tiny fragment of diamond — a "seed" — and both reproduce the conditions that form diamonds underground.
HPHT
High Pressure, High Temperature
The seed is placed in a press and subjected to roughly 1,500°C and 60,000 atmospheres — approximating the conditions around 150km below the earth's surface. Carbon deposits onto the seed and crystallises. This method typically produces stones with a slightly warmer tone.
CVD
Chemical Vapour Deposition
The seed sits in a chamber filled with carbon-rich gas, heated to around 800°C. The gas breaks down and pure carbon deposits onto the seed layer by layer. This method tends to produce higher color grades and is the more common process today.
A rough lab-grown diamond takes roughly two to four weeks to grow. A mined diamond takes one to three billion years — and a great deal of earth moved to find it.
Certification
Graded on the same scale as mined stones.
Lab-grown diamonds are graded by the same independent laboratories, using the same four criteria — the "4Cs" — applied to mined diamonds. The report exists for the same reason: so you know precisely what you're buying without taking anyone's word for it.
We don't work with suppliers who won't certify. Every center stone over 0.5ct ships with its report, and we send you a photograph of the actual stone before it's set.
The four Cs
- Cut
- The most important factor for brilliance — how well the facets are angled to return light. A well-cut stone outshines a larger poorly-cut one.
- Color
- Graded D to Z, where D is colorless. Lab-grown stones are often graded D–F, since the process can be controlled more tightly than nature.
- Clarity
- Rated from Flawless to Included, describing internal inclusions and surface blemishes visible under 10x magnification.
- Carat
- Weight, not size — though the two correlate. One carat equals 200 milligrams. Spread depends on the cut.
Comparison
What actually differs.
| Lab-grown | Mined | |
|---|---|---|
| Chemical composition | Pure carbon | Pure carbon |
| Mohs hardness | 10 | 10 |
| Refractive index | 2.42 | 2.42 |
| Origin | Grown in weeks | Formed over billions of years |
| Relative price | Substantially lower | Substantially higher |
The first three rows are the ones that matter for how a stone looks and wears. They're identical.
Ready to choose your stone?
Browse the collection, or tell us what you have in mind and we'll come back with options against your budget.