The best lab grown diamonds aren’t about chasing the top of every grade, they’re about balancing the 4Cs the right way and insisting on certification. Get cut excellent, colour near-colourless, clarity eye-clean, and an IGI or GIA report, and you’ll have a beautiful stone without overpaying. Here’s how to judge quality in 2026, the way I do it for every client.
I’m Suman Smith, founder of Lux Jewels. I started this as Canada’s first lab grown diamond company back in 2015, and I hand-select every stone we set. Let me show you what separates a great lab grown diamond from an ordinary one.
Quick Answer
The best lab grown diamonds have an Excellent cut, G to H (near-colourless) colour, VS to SI (eye-clean) clarity, and an IGI or GIA certificate. Cut matters most for sparkle. You don’t need flawless or colourless, you need the right balance plus proof of grading.
What makes a high quality lab grown diamond?
The same things that make any diamond high quality: the 4Cs and a credible certificate. A lab grown diamond is a real diamond, chemically and optically identical to a mined one and graded on the same scale, so quality is judged exactly the same way. The advantage is price, with no mined markup, your budget reaches a better combination of the 4Cs.
The quality grades to aim for
Here’s the sweet spot I recommend for beautiful results that don’t waste money on grades you can’t see.
| Quality factor | Aim for |
|---|---|
| Cut | Excellent (Very Good minimum). The most important C. |
| Colour | G to H, near-colourless and looks white to the eye. |
| Clarity | VS1 to SI1, eye-clean with no visible inclusions. |
| Certificate | IGI or GIA report, always. |
Why certification matters most
A certificate from IGI or GIA is your independent proof of the 4Cs, so you’re buying graded quality, not a seller’s word. Every reputable lab grown diamond comes with one, and you should never buy a stone without it. The report confirms the cut, colour, clarity, carat, and that the diamond is lab grown, so there are no surprises.
Are all lab grown diamonds the same quality?
No. Just like mined diamonds, lab grown stones range from poor to superb across the 4Cs, so two lab grown diamonds of the same size can look completely different. That’s why hand-selection matters: I choose stones that are eye-clean, well-cut, and bright, and skip the ones that look dull or have visible flaws. The lab grown label alone isn’t a quality guarantee, the grading and the eye are.
Want a hand-selected, certified stone?
Book a private video call with Suman and we’ll review the 4Cs on real certified lab grown diamonds together, so you get genuine quality for your budget. No markup games, no sales pressure.
$199 | 30 minutes | Video call
How to get the best value
Spend on cut first, since it drives the sparkle you actually see, then sit at G or H colour and VS to SI clarity rather than paying for flawless or colourless. Buy just under round carat marks to save, and choose an elongated shape or a halo if you want more visible size. Because lab grown costs far less per carat, this strategy gets you a noticeably better diamond than the same budget would buy in mined. See our full 4Cs of diamonds guide.
The honest takeaway
The best lab grown diamonds lead with cut, sit at near-colourless and eye-clean, and always come with an IGI or GIA certificate. Don’t pay for grades you can’t see, and don’t assume every lab grown stone is equal, it isn’t. If you’d like a hand-selected diamond chosen for genuine beauty and value, that’s exactly what our consultation is for.
Frequently asked questions
What makes a lab grown diamond high quality?
An Excellent cut, near-colourless colour (G to H), eye-clean clarity (VS to SI), and an IGI or GIA certificate. Cut matters most because it controls sparkle.
What colour and clarity should I choose?
G or H colour looks white to the eye for far less than D to F, and VS1 to SI1 clarity is eye-clean. Past those points you pay for grades only a loupe can see.
Are all lab grown diamonds the same quality?
No. They range from poor to superb across the 4Cs, just like mined diamonds. Two stones of the same size can look very different, which is why grading and hand-selection matter.
Do lab grown diamonds come with a certificate?
Reputable ones do, from IGI or GIA. The report confirms the 4Cs and that the stone is lab grown. Never buy a diamond without a certificate.
Do I need a flawless, colourless diamond?
No. Flawless and colourless grades cost much more without a visible difference to the eye. Eye-clean and near-colourless give the same look for far less, so put the savings into cut and size.
Related reading: our certified lab grown diamonds, the 4Cs of diamonds, diamond clarity chart, and diamond colour scale.
