A practical primer for jewelers, retailers, and the customers they sell to. What lab-grown is, how it's made, and what to look for when you buy.
A lab-grown diamond is a real diamond — chemically, physically, and optically identical to a mined diamond. The only difference is where it came from. Instead of being pulled out of the ground, it is produced inside a controlled environment, typically using one of two processes: CVD (Chemical Vapor Deposition) or HPHT (High Pressure High Temperature).
Both processes produce the same end material: pure crystallized carbon, scoring 10 on the Mohs hardness scale, with the same refractive index and fire as a mined diamond. They are not simulants. They are not cubic zirconia. They are diamond.
CVD growth begins with a thin seed — a small slice of existing diamond. The seed is placed inside a sealed reactor, which is then filled with a carbon-rich gas, usually methane. The gas is energized into a plasma using microwave or filament heating, which breaks the methane molecules apart and allows carbon atoms to settle onto the seed.
Layer by layer, atom by atom, a new diamond grows. Over several weeks, what starts as a tiny seed becomes a rough crystal large enough to cut into a polished gemstone. From there, the rough is planned, cut, and polished exactly the way a mined rough would be.
| Lab-Grown | Mined | |
|---|---|---|
| Material | Crystallized carbon | Crystallized carbon |
| Hardness (Mohs) | 10 | 10 |
| Optical properties | Identical to mined | Identical to lab-grown |
| Origin | Controlled reactor | Mining operation |
| Grading | Same 4Cs as mined | Standard 4Cs |
| Traceability | Reactor → polish → ship | Often opaque past first sale |
| Typical wholesale price | Lower per carat | Higher per carat |
Weight, not size. One carat equals 0.2 grams. Two stones of the same carat weight can look different sizes depending on how they're cut.
Graded D (colorless) through Z (light yellow or brown). Most fine jewelry uses D–I. CVD growth can produce stones in the colorless D–F range reliably, which is part of why the technology took off.
How free of inclusions a stone is. The grading scale runs FL (flawless) through I (included). CVD stones tend to have very specific inclusion patterns — graders are trained to recognize them.
Often the single biggest driver of how a stone looks. A well-cut stone with average color will out-perform a poorly cut stone with top color. Cut grades run Poor through Excellent / Ideal.
The two labs most commonly used for lab-grown grading are IGI and GIA. A certified stone arrives with a printed or digital report that documents its 4Cs, measurements, polish, symmetry, and any treatments. Certified stones typically also carry a laser-inscribed report number on the girdle.
Non-certified stones are graded in-house using the same parameters, but without the third-party report. They are common in melee, smaller sizes, and jewelry that's being set immediately rather than sold loose.
There isn't a hard minimum. We've shipped single test stones to new accounts and we've shipped six-figure parcels to repeat ones. We care more about a good fit than a number on the first invoice.
Most U.S. domestic orders ship within 48 hours, fully insured, with tracking. International turnaround depends on destination and customs, typically 5–10 business days.
Yes, for qualified accounts. After the first one or two paid orders, we're comfortable extending memo on individual stones so you can review them in hand before committing.
That's most of what we do. Send us a sample stone or a tightly written spec — shape, size range, color, clarity, polish, symmetry — and we'll come back with calibrated options.
Our core production is CVD. We can source HPHT on request for specific use cases, and we'll always tell you which process produced a given stone.
Per-carat wholesale on lab-grown is meaningfully lower than mined for equivalent specs, and it has stabilized in the last few cycles. We're happy to share current price sheets with active wholesale accounts.
Yes — IGI is standard and turns around quickly; GIA is available with a slightly longer lead time. We pass through the cert fee at cost.
Send them over — we'd rather take a real question from a real buyer than write generic copy that doesn't help anyone.