Discover how diamond testers work, whether lab grown diamonds test as real diamonds, and how jewellers can tell the difference.
Diamonds have changed a lot over the last few years. One of the most common questions we hear in-store is:
"Will a lab grown diamond pass a diamond tester?"
The short answer is:
Yes — most standard diamond testers will identify a lab grown diamond as a real diamond.
That's because lab grown diamonds are not imitation stones. They are genuine diamonds with the same chemical composition, hardness and thermal conductivity as natural diamonds.
However, the full answer is a little more complicated.
Can you tell which is which? To the naked eye, most people can't.
Read to the end for the answer.
What does a diamond tester actually test?
Most traditional diamond testers measure how efficiently a stone conducts heat.
Diamonds conduct heat extremely well, which is one of the reasons they can be distinguished from common diamond simulants such as:
- Cubic Zirconia (CZ)
- Glass
- Crystal
- Most synthetic gemstones
Because lab grown diamonds have the same physical properties as natural diamonds, a standard diamond tester will usually indicate that both stones are diamonds.
So if you're using a basic handheld tester, a lab grown diamond will almost always "pass."
Can jewellers tell the difference?
Many jewellers, particularly those focusing on lab-grown diamonds, will tell you "even jewellers cant tell the difference"
Which, to an extent is true.
To the naked eye, natural and lab grown diamonds look virtually identical. Both offer:
- The same sparkle
- The same hardness (10 on the Mohs scale)
- The same durability
- The same chemical structure
However, modern professional diamond testing equipment can identify whether a diamond is natural or lab grown.
At Eloise Jewellery, we use specialist diamond testing equipment that allows us to accurately determine whether a diamond is natural or laboratory-grown.
This is important when buying, selling, valuing or remodelling diamond jewellery. Which are all services we offer.
Why do lab grown diamonds pass basic testers?
Lab grown diamonds are created using advanced technology that replicates the conditions under which natural diamonds form.
The result is a genuine diamond rather than an imitation stone.
This means a lab grown diamond will typically:
✅ Pass a thermal diamond tester
✅ Pass many electrical conductivity tests
✅ Display the same brilliance and fire
✅ Have the same durability as a natural diamond
The main difference is where the diamond was formed, not what it is made from.
Natural diamonds vs lab-grown diamonds
At Eloise Jewellery, we have traditionally specialised in natural diamonds and continue to stock and source a wide range of beautiful natural diamond jewellery.
However, due to customer demand, we can also source lab-grown diamonds in virtually any:
- Size
- Shape
- Colour
- Clarity
- Carat weight
Whether you're looking for a natural diamond or a lab-grown diamond, the most important thing is choosing the option that suits your budget, preferences and values.
Popular diamond jewellery at Eloise
If you're looking for lab-grown diamond jewellery, you may enjoy browsing:
💍 Classic Platinum Pear-Shaped Lab Grown Diamond Engagement Ring
💍 Timeless Platinum Oval-Cut Lab Grown Diamond Engagement Ring
💎 9ct White Gold Compass Set Lab Grown Diamond Solitaire Necklace
Or if you'd like something completely unique, our bespoke design service allows us to create a custom diamond ring tailored specifically to you.
What if I already own a diamond?
If you've inherited a diamond, purchased one elsewhere, or simply want to know exactly what you have, professional testing can provide clarity.
We can also help if you're considering:
- Creating a bespoke engagement ring
- Remodelling inherited jewellery
- Replacing a lost diamond
- Upgrading an existing ring
- Having your jewellery assessed by an experienced jeweller
Handmade By Us
What our customers say
⭐ Vix Ottiwell
"I spent ages looking for the perfect engagement ring I found Eloise and wish I had known about it before! They didn't have my perfect ring so they made it for me! I'm so happy with it! Thank you all so much for making it! It was fast too!"
⭐ Sara Buchan
"Was taken there today by my fiancé to choose a piece of jewellery for a special birthday, the lovely lady was so helpful and I absolutely cannot wait to wear my beautiful ring and show it off."
Final verdict
Yes, a lab-grown diamond will usually pass a standard diamond tester because it is a real diamond.
However, modern professional testing equipment can identify whether a diamond is natural or lab-grown.
If you're unsure about a diamond you own, or you're considering purchasing a natural or lab grown diamond, we're always happy to help explain the differences and guide you towards the best option for your needs.
Visit or Contact Eloise Jewellery
📍 Eloise Jewellery
156 High Street
Kirkcaldy, Fife, Scotland
KY1 1NQ
📞 01592 646340