Buying a diamond can get overwhelming surprisingly quickly.
You start off thinking, "I’d quite like a diamond."
Then suddenly you're comparing D with G, VS1 with VVS2, wondering whether 1.8 carats is secretly better value than 2 carats and trying to work out whether you need a certificate for a stone that apparently already comes with a small novel's worth of specifications.
If you’ve found yourself there, you're not alone.
When I help someone choose a lab-grown diamond or natural diamond for a custom engagement ring, my job isn't to convince them to buy the biggest or highest-grade stone they can afford. It's to help them understand what they’re looking at, decide what actually matters to them and spend their money where they’ll notice the difference.
So, let’' make diamonds a little less complicated.
Is a lab-grown diamond a real diamond?
Yes.
A lab-grown diamond is a diamond.
It has essentially the same chemical, physical and optical properties as a natural diamond. The main difference is how it came into existence.
A natural diamond formed deep within the earth over millions or billions of years. A lab-grown diamond was created in a controlled environment using technology that replicates the conditions in which diamonds form.
They can look identical to the naked eye. Reliably distinguishing between the two requires specialist equipment and expertise.
So lab-grown diamonds aren't cubic zirconia, moissanite or diamond imitations.
They're diamonds.
Whether you prefer the geological history of a natural diamond or the price and sourcing possibilities of a lab-grown diamond is a personal decision. I don't think there's one universally "right" choice.
There's just the right choice for you.
The 4Cs of lab-grown diamonds
You’ve probably heard about the 4Cs:
- Cut
- Color
- Clarity
- Carat
These are the characteristics traditionally used to describe and evaluate a diamond and they’re useful whether you're considering a natural or lab-grown stone.
The trick is understanding that you don't necessarily need the highest grade in every category.
In fact, I often wouldn't recommend it.
A specification on a piece of paper is one thing. What the diamond actually looks like on your hand is another.
Diamond cut, the one I really don’t like compromising on
Cut is often confused with shape.
Round, oval, emerald, pear and cushion are shapes.
Cut is about how well the facets and proportions of the diamond interact with light.
And it matters. A lot.
You can have a diamond with exceptional color and clarity but if it’s poorly cut, it can still look rather disappointing. A beautifully cut diamond reflects light back through the top of the stone, creating the brightness, fire and sparkle we associate with diamonds.
So if we're deciding where to put the budget, cut is high on my list.
I would much rather help you find a beautifully cut diamond with slightly lower color or clarity than a technically impressive D Flawless diamond that doesn't come alive when you look at it.
Because unless you're planning to walk around handing people a loupe and your grading report, what you actually see matters.
Diamond color, how white does it need to be?
For colorless and near-colorless natural diamonds, the familiar GIA scale runs from D to Z.
D, E and F are considered colorless while G, H, I and J are near-colorless. As you move further down the scale, warmer yellow or brown tones become increasingly noticeable.
But the difference between neighboring color grades can be incredibly subtle, particularly once the diamond is set.
The metal you choose can make a difference too. A little warmth in a diamond may be more noticeable against platinum or white gold while yellow or rose gold can be much more forgiving.
Size and shape can also affect how color presents itself.
So do you automatically need a D?
No.
If having a truly colorless diamond is important to you, wonderful. We can prioritize that.
But if you can’t see a meaningful difference between two stones with your own eyes, I'd rather have a conversation about whether that extra money could be better spent elsewhere.
Maybe on the cut.
Maybe on a slightly larger stone.
Maybe on the setting.
Or maybe on a really good dinner after you pick up the ring.
Diamond clarity, how perfect does it really need to be?
Diamonds have internal characteristics called inclusions and external characteristics called blemishes.
Clarity grading considers things such as their size, number, position and nature, generally under 10x magnification.
The traditional clarity scale runs from Flawless and Internally Flawless through VVS, VS and SI grades to Included diamonds.
This is another area where it's very easy to pay for perfection you can't actually see.
A VS diamond, for example, has minor inclusions that are assessed under magnification. Depending on the individual stone, those inclusions may be extremely difficult or impossible for you to see without magnification.
You'll sometimes hear the term eye-clean. It isn't an official GIA grade. It simply means the inclusions aren't visible to the naked eye under normal viewing conditions.
For many of my clients, that's a much more useful question.
Can you see the inclusion?
Does it affect the beauty of the stone?
Could its position affect the durability of the diamond?
If the answers are no, no and no, do you really need to pay substantially more for VVS or Flawless?
Maybe you do because knowing that level of rarity is important to you. There's nothing wrong with that.
But I want you to know what you're paying for.
Diamond carat, which is weight, not size
This one catches people out.
Carat measures the weight of a diamond, not its physical dimensions. One carat equals 0.2 grams.
Two diamonds can have exactly the same carat weight and still look different in size when viewed from above because of their proportions and shape.
This is why I never like looking at carat weight in isolation.
There are also price jumps around popular carat weights such as 1, 1.5 and 2 carats. Sometimes choosing a stone just under one of those numbers can give you almost the same visual presence without paying for the psychological satisfaction of a nice round number.
Your finger, thankfully, has no idea what the certificate says.
So where should you spend your money?
This depends entirely on you, which is why I enjoy sourcing stones for custom pieces rather than working from a rigid formula.
Generally, though, I would prioritize:
- A great cut
- A color you’re happy with
- A clarity where inclusions don’t detract from the stone
- The size that feels right on your hand and works with your budget
Notice I said feels right, not "the biggest diamond you can possibly afford".
Those aren't necessarily the same thing.
What is the best color and clarity for a lab-grown diamond?
This is one of those questions where I wish I could give you a neat answer.
Something like "G color, VS2 clarity. Done. Next question."
Unfortunately, diamonds don't really work like that.
The best color and clarity depend on the individual diamond, its shape, size, setting and, most importantly, what you can actually see.
For clarity, I generally care far more about whether a diamond is eye-clean and whether any inclusions could affect its appearance or durability than I do about chasing the highest grade on the report.
Color is similar. If you put two diamonds next to each other and can’t see a meaningful difference in color, I’d question whether spending more for the higher grade is really where you want your budget to go.
That's why I prefer looking at the whole diamond rather than choosing one because a collection of letters and numbers looks impressive.
The report helps us narrow down the options.
Your eyes help us choose the diamond.
Why choose a lab-grown diamond?
One of the biggest attractions of lab-grown diamonds is price.
Generally, your budget will buy you a significantly larger or higher-specification lab-grown diamond than an equivalent natural diamond.
That can be wonderful if size is important to you or if you'd rather put more of the budget towards the custom setting, wedding, honeymoon, house deposit or something else entirely.
Lab-grown diamonds can also appeal to people who would prefer not to buy a newly mined stone.
But I think we need to be careful about automatically calling lab-grown diamonds "sustainable".
Growing diamonds requires energy. How that energy is generated varies between producers and locations, so the environmental picture isn't as simple as "mined bad, lab good".
If environmental impact is important to you, ask questions about where the diamond was grown and the energy used to produce it.
I'd much rather give you a complicated truthful answer than a beautifully packaged green one.
Lab-grown vs natural diamonds
For some people, the fact that a natural diamond was formed in the earth over an almost incomprehensible amount of time is part of its magic.
Natural diamonds are finite geological objects and that rarity is reflected in their price.
If the history, rarity and natural origin matter deeply to you, then a natural diamond may absolutely be worth the additional cost.
If they don't, you may decide you'd rather have a larger lab-grown diamond for the same budget.
Neither choice makes your ring more meaningful.
That bit comes from you.
What about resale value?
This is worth talking about because I don't like surprises, particularly expensive ones.
Lab-grown diamonds have become significantly more affordable as production has expanded and technology has improved. That's good news when you're buying one.
It also means I would not recommend buying a lab-grown diamond because you expect it to hold its purchase price or increase in value.
Natural diamonds have a more established secondary market but I wouldn't encourage you to think of a typical engagement-ring diamond as a financial investment either. Retail price and resale value are very different things.
Buy the diamond because you love it and because it works for your piece and your budget.
Do you need a certificate for a lab-grown diamond?
First, a tiny bit of terminology.
We commonly call them diamond "certificates", but grading report is generally the more accurate term.
A grading report is an independent assessment of a diamond. Depending on the laboratory and type of report, it can document whether the diamond is natural or laboratory-grown along with characteristics such as measurements, carat weight, color, clarity, cut, polish and symmetry.
For a significant center stone, I think having independent documentation is worth it.
It tells us what the stone actually is and gives us an objective starting point when comparing diamonds.
GIA vs IGI for lab-grown diamonds
Two names you’ll see frequently when looking at diamond grading reports are GIA, the Gemological Institute of America and IGI, the International Gemological Institute.
Both assess laboratory-grown diamonds, but there is an important difference in how their current reports work.
Since October 2025, GIA has changed the way it assesses colorless-to-near-colorless lab-grown diamonds. Instead of the traditional individual color and clarity grades used for natural diamonds, qualifying stones receive an overall Premium or Standard quality assessment.
IGI currently uses the more familiar grading system for its lab-grown diamond reports, documenting the 4Cs individually and identifying the stone as laboratory-grown.
So if you’re comparing lab-grown diamonds and the paperwork looks different, don’t panic. Check who issued the report and what grading system they’re using.
Neither piece of paper can tell you whether you actually love the diamond.
That's still your job.
What if you supply the diamond for your custom ring?
This is where a grading report becomes particularly important.
If you purchase a loose center diamond yourself and bring it to me to set into a custom piece, I strongly recommend buying one that already has an independent grading report from a reputable laboratory such as GIA or IGI.
Why?
Because before I take possession of your diamond, we both have independent documentation of exactly what that stone is.
When I return your finished ring, there’s no question about whether the diamond in your ring is the diamond you gave me.
I trust you. You trust me.
And paperwork means neither of us has to rely on trust alone.
For a valuable stone, that's a very good thing.
What if I source the diamond for you?
If I'm sourcing a substantial center diamond for your custom piece, I would generally source one with independent documentation too.
It gives us an objective starting point when comparing stones and means I can show you exactly what you’re buying.
For tiny side stones, accent diamonds or pavé, individual grading reports generally aren’t practical or necessary.
If you particularly want independently documented side stones, we can discuss it, but it isn't something I would normally tell you that you need.
What are the pros and cons of a diamond grading report?
The advantages are fairly straightforward.
You have independent verification of the diamond’s characteristics, confirmation of whether it's natural or lab-grown and documentation that can help identify the stone.
It gives us a useful basis for comparing diamonds and creates a clear record if you're handing your own stone to me for a custom piece.
It can also provide useful supporting documentation when you arrange an appraisal or insurance.
The downside?
There's a cost. Not every small diamond warrants the expense and sending an existing diamond away for grading can add time and cost to a project.
And a grading report still doesn't tell you whether you actually like the diamond.
That last bit matters.
Two diamonds can look remarkably similar on paper and very different when you put them next to each other.
Diamond grading report vs appraisal
A diamond grading report describes the diamond and its gemological characteristics.
An appraisal places a monetary value on the finished piece or stone, usually for a particular purpose such as insurance.
They're not interchangeable.
If you have a valuable custom engagement ring, I recommend speaking with your insurer about exactly what documentation they require. Depending on the insurer and value of the piece, that may include an independent appraisal, your receipt and the diamond grading report.
And please actually insure the ring.
I know. Insurance paperwork is considerably less exciting than designing an engagement ring.
But so is discovering your ring isn't covered after you've lost it.
How to choose the right diamond for you
This is the part where I disappoint you by not giving you a magic combination of letters and numbers.
There isn't one.
Your perfect diamond might be a 1.5 carat natural diamond because its history and rarity mean something to you.
It might be a 2.5 carat lab-grown diamond because you've always wanted that visual impact and you’d rather not spend the equivalent natural-diamond price.
You might care enormously about color but not about microscopic inclusions.
You might want an unusual shape rather than the largest possible carat weight.
Or you might come to me with absolutely no idea what any of this means and say, "Jo, please just help me."
That's allowed too.
When I source a diamond for a custom piece, I'm not looking for the most impressive grading report I can find.
I'm looking for the right stone for you.
The right proportions. The right visual character. The right quality. The right price. And ultimately, the one that makes sense for the piece we’re creating together.
Because the 4Cs are useful.
The grading report is useful.
The numbers are useful.
But they're tools to help you choose your diamond.
They're not the reason you're going to love your ring.
Thinking about a custom diamond ring?
If you're considering a lab-grown or natural diamond for an engagement ring or another custom piece, you don’t have to work all of this out before getting in touch.
That's part of my job.
We can talk about what matters to you, what doesn't, your budget and how you actually want the finished piece to look and feel. Then I can help you navigate the options without trying to convince you that you need the most expensive stone on the page.
Because you probably don't.
You just need the right one.
Ready to start your custom piece?
Get in touch and let's talk about what you'd like to create.