You've done your research. You know lab-grown diamonds are real diamonds: same carbon structure, same brilliance, same hardness. But when you start shopping, the grading terminology can feel a bit overwhelming.
What exactly does a jeweler look for? And does grading work the same way as it does for mined stones?
Short answer: yes, completely. Here's exactly how it works.
Lab-Grown Diamonds Are Graded Like Any Real Diamond
Lab-created diamonds go through the same grading process as mined ones. There's no separate rulebook for them.
Reputable gemological labs, most notably the International Gemological Institute (IGI), evaluate every stone using a universal standard. At House of Quadri, all our lab-grown diamonds come with IGI certification, so you always know what you're buying.
The 4Cs: The Foundation of Diamond Grading
Every diamond, whether grown in a lab or formed over billions of years underground, is assessed on four criteria. These are called the 4Cs of diamonds.
1. Cut
Cut is arguably the most important of the four. It refers to how well the diamond has been shaped and faceted, not the shape itself (round, oval, pear, etc.), but the precision of the proportions and angles.
A well-cut diamond reflects light beautifully. A poorly cut one, even with great clarity and colour, will look dull.
Grades range from: Excellent, Very Good, Good, Fair, Poor.
At House of Quadri, we prioritise excellent and very good cuts because that's where the sparkle lives.
2. Clarity
Clarity measures the presence of internal inclusions or surface blemishes. Even man-made diamonds can have slight internal characteristics formed during the growth process.
The clarity scale runs from:
- FL / IF (Flawless / Internally Flawless) - virtually perfect
- VVS1 / VVS2 (Very Very Slightly Included) - minuscule inclusions
- VS1 / VS2 (Very Slightly Included) - minor inclusions, not visible to the naked eye
- SI1 / SI2 (Slightly Included) - noticeable under magnification
- I1 / I2 / I3 (Included) - visible inclusions
For everyday fine jewellery, VS1 to VS2 hits the sweet spot of beauty and value.
3. Colour
Diamonds are graded on a colour scale from D (colourless) to Z (light yellow/brown). The closer to D, the rarer and more premium the stone.
Here's something worth knowing: many of our white lab-grown diamonds achieve the Type IIa classification, a purity rating held by fewer than 2% of mined diamonds. That means exceptional colourlessness and brightness, without the rarity premium.
4. Carat
Carat refers to the weight of the diamond, not the size. One carat equals 0.2 grams.
Because lab-created diamonds skip the supply chain markups of mining, you can often go up a carat grade without stretching your budget. That's just practical luxury.
What Makes Lab-Grown Diamond Grading Different?
In one key way, it's actually more rigorous.
Because lab-grown diamonds are newer to the fine jewellery market, certification labs are especially thorough. IGI, for instance, also notes the growth method (CVD or HPHT) on the grading report. This adds a layer of full transparency you don't always get with mined stones.
There's no ambiguity. You receive a report that tells you exactly what you have.
Why Certification Is Non-Negotiable
A grading report is your proof. It confirms the stone's 4C values, confirms it's a real diamond, and gives you documented value for insurance or future exchange.
Any reputable seller of lab-grown diamonds will provide certification. If they don't, that's your sign to walk away.
All 1-carat or above solitaires at House of Quadri come with IGI certification as standard. House of Quadri Uses Only IGI Certified Lab-Grown Diamonds. No fine print, no asking for it separately.
How Grading Affects Price
Here's where lab-grown diamonds make a genuinely compelling case.
The grading standards are identical to mined diamonds. But because the supply chain is more efficient, a lab-grown diamond at VS1 clarity, E colour, excellent cut, and 1.5 carats will cost a fraction of what a comparable mined stone would. See how lab-grown diamonds compare to natural ones in more detail.
You get the grade. You get the certification. You get the sparkle at a price that makes sense.
Who Should Care About Grading?
Honestly, everyone buying a diamond should understand this, whether it's for an engagement ring, a daily wear band, or a gift.
Knowing the 4Cs means you shop with confidence, not guesswork. And when you buy a certified lab-grown diamond, you're making a choice backed by science, ethics, and real documented value.
If you're curious about why younger buyers, especially, are drawn to this, this blog on why Gen Z and millennials love lab-grown diamonds is worth a read.
FAQs
Are lab-grown diamonds graded the same as natural diamonds?
Yes. The same 4C standards and gemological institutions apply.
What is an IGI certificate for lab-grown diamonds?
It's a grading report confirming the diamond's 4Cs and growth method, your proof of quality and value.
Is a higher clarity grade always better?
Not always. VS1 and VS2 inclusions are invisible to the naked eye and offer better value without any visual compromise.
Do man-made diamonds hold their grading over time?
Yes. A diamond's physical properties are permanent, and so is its IGI report.
Why does cut matter more than other grades?
Cut controls how the diamond handles light. It's where the sparkle actually comes from.
Final Thoughts
Grading a lab-grown diamond is not complicated once you know what to look for. The 4Cs give you an objective, documented way to compare stones, and certification makes sure nothing is left to guesswork.
Whether you're buying for a milestone or simply treating yourself, understanding these grades puts the power back in your hands. You know exactly what you're getting, and you're getting it at a price that reflects real value.
That's the kind of clarity that goes beyond the stone itself.
At House of Quadri, every lab-grown diamond we sell is IGI-certified and crafted in 18K gold. Brilliant by nature, honest by design.