Learn
Lab-grown diamond guide
Everything you need to buy a lab-grown diamond with confidence, in plain words.
The basics
What is a lab-grown diamond?
A lab-grown diamond is a real diamond. It is made of the same pure carbon, in the same crystal structure, as a diamond from the ground, so it has the same hardness, sparkle and chemistry.
Instead of forming deep underground, it is grown in a lab under carefully controlled conditions, using one of two methods: CVD (carbon is built up layer by layer from a gas) or HPHT (high pressure and high temperature, like deep in the earth). Either way, the result is diamond. It is then cut and polished exactly like a mined one.
Compare
Lab-grown vs mined vs moissanite
Lab-grown and mined diamonds are the same material. Moissanite only looks similar.
| Lab-grown diamond | Mined diamond | Moissanite | |
|---|---|---|---|
| What it is | Diamond (pure carbon crystal) | Diamond (pure carbon crystal) | Silicon carbide, a different mineral |
| Hardness (Mohs) | 10 | 10 | 9.25 |
| Look | Diamond sparkle | Diamond sparkle | Stronger rainbow flashes |
| Where it forms | In a lab | Underground, then mined | In a lab |
| Graded on the diamond 4Cs | Yes, by labs like IGI | Yes, by labs like IGI | No, it is not a diamond |
| Price for the same look | Much lower than mined | Highest | Lowest |
Grading
The 4Cs, simply
Every diamond, lab-grown or mined, is graded on the same four things.
-
Cut
How well the diamond is cut and polished. A good cut returns light to your eye, which is what makes a diamond sparkle.
-
Color
How colorless the diamond is, graded from D (colorless) down the alphabet. D to F look icy white; G and H still look white to most eyes.
-
Clarity
How few tiny marks (inclusions) the diamond has. VVS means very, very slightly included; VS means very slightly included. Both look clean to the naked eye.
-
Carat
The diamond’s weight. One carat is 0.2 grams. For jewelry with several stones, total carat weight is all the diamonds added together.
Certification
What an IGI report tells you
IGI (International Gemological Institute) is an independent gem lab. Its report records a diamond’s grades, such as carat weight, color and clarity, and states that it is lab-grown.
We use IGI-certified diamonds. The certification details for each piece are on its product page, so you can check them before you order.
Diamond questions
Are your diamonds real?
Yes. A lab-grown diamond is a real diamond: the same pure carbon crystal as a mined diamond, with the same hardness, sparkle and chemistry. The only difference is where it formed: in a lab instead of underground.
Is it moissanite or cubic zirconia?
No. Every stone we use is a lab-grown diamond. Moissanite is a different mineral (silicon carbide) and cubic zirconia is a diamond look-alike. Neither is a diamond.
Will it pass a diamond tester?
Yes. A standard diamond tester reads a lab-grown diamond as diamond, because it is one. Specialist lab equipment can tell lab-grown from mined, which is why lab-grown diamonds are always sold as lab-grown.
Can I wear it every day?
Yes. Diamond is the hardest material used in jewelry (10 on the Mohs scale), so it is made for daily wear. Like any fine jewelry, take it off for the gym, heavy work, swimming pools and cleaning products. See our jewelry care tips.
How do I choose the diamond quality?
Where a piece offers a choice of diamond quality, the color and clarity of each option are shown on the product page. Our lab-grown diamond guide explains what the grades mean in plain words.
Real diamonds, factory prices.
IGI-certified lab-grown diamonds, handcrafted to order and shipped free and fully insured.
Today’s sale window ends in