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Will A Lab-created Diamond Pass A Diamond Tester?

Will A Lab-created Diamond Pass A Diamond Tester?

If you have recently been to a jewelry store or are familiar with the gem business, you surely know how essential diamond testers must be. These are not just your average testers; they are in charge of checking the authenticity and electrical conductivity of the diamond. 

However, natural mined diamonds are not the only ones that can end up in the jewelry store. People are also into buying and selling lab-created diamonds. 

The thing that interests you today is can lab-created diamonds pass a diamond tester? That’s a tricky question to answer in just one sentence. We’re gonna need more time if you want a fully detailed answer.

There are several criteria you need to check before you proudly display your diamond in your shop window. So, if you are eager to find out more helpful information on the topic of diamond testing, don’t hesitate to scroll down! 

How Does A Diamond Tester Work? 

A diamond tester is a small device that is used to check the authenticity and electrical conductivity of a diamond. You can find at least one of these gadgets in every jewelry store.

In addition to the personal experience that you possess, this is probably the most reliable device you can have. If you are in this business, this is necessary.

So, how does a diamond tester work, and is it easy to manage?

Firstly, there are two types of diamond testers. One is sensitive to heat, and the other one to electricity.

The first type registers different levels of heat, according to which it will tell you whether your diamond is real or fake. The other type functions in the same way, just with electricity levels. 

Both of these are similar, and they are easy to handle. 

Learn More:

Lab-Created Diamonds: Pass Or Fail?

You’d be pleased to find out that lab-created diamonds can pass the diamond tester – in most cases, that is. We didn’t say 100% because there are poorly made diamonds that lack some essential characteristics.

For example, carbon lab diamonds will undoubtedly pass the physical appearance portion of the test. However, when it comes to composition and electrical conductivity, experts will likely be able to find flaws very easily.

In addition to those diamonds that passed the test – both lab-made and mined – you have the standard fake ones. A fake diamond is virtually impossible to pull through due to the experts’ immense precision and attention to detail.

Years in this business will allow you to see many different types of diamonds. But it will also enable you to identify those that will certainly not pass the test.

Carbon lab diamonds are not the only ones you’ll find on the market these days. There are many types – and that’s going to be our next topic.

Related Read:

Lab-Created Diamond: Types

There are two main types of lab-created diamonds, and these are stimulant and cultured diamonds. Each group has a couple of subtypes, but the main difference in these two can be summed up as follows:

Stimulant diamonds are not made from scratch. The root of their making lies in the laboratory. Their chemical and physical composition is quite different from mined diamonds, but that can only be seen by careful examination.

On the other hand, the root of cultured diamonds is found in nature, and all scratch is 100% natural. Another thing that helps one see the difference is that these diamonds are embossed with a number so that they are not used for resale purposes.

Now, it’s time to briefly go through the subtypes.

Simulated diamonds:

  1. Diamond Nexus Simulant – The main part of this diamond is carbon (the one I mentioned a while ago).
  2. Cubic Zirconia Simulants – This is the least pricey simulated diamond on the market.
  3. Moissanite Lab created gemstones – Besides the difference in appearance, it is very valuable.

Cultured diamonds:

  1. HPHT diamonds – The abbreviation stands for high-pressure and high-temperature. There are three major designs regarding this diamond (cubic, split-sphere and belt press).
  2. CVD diamonds – Chemical vapour deposition diamonds are made from a carbohydron mixture.

Related Read: What Is The Difference Between HPHT And CVD?

The 4Cs of Diamonds – Explained

By now, you’ve probably heard about the 4Cs as a way of rating diamonds. If you haven’t, now is the perfect time to update your already existing knowledge on this topic. To put it simply, the 4Cs stands for:

That sounds familiar, doesn’t it?

You’ve probably seen jewelers with their specially equipped goggles studying the diamond you brought to the jewelry store. Well, they’re doing exactly what we’re about to explain, so let’s get right to it.


As the name suggests, this criterion refers to the purity and transparency of the diamond. Minor blemishes and inclusions are almost invisible to the naked eye, so it is essential to evaluate this aspect of the diamond carefully.

To simplify this, jewelers developed a clarity scale, by which the clearest diamond is rated FL – flawless. 

Related Read: Do SI Diamonds Pass Diamond Tester?


A diamond that the jeweler expects to sell quickly should be beautiful and high-quality – and that also implies a precise cut. Hence the criteria – cut grading.

Diamonds can come in a variety of shapes, and that shouldn’t confuse anyone who grades them. No matter what shape it comes in, whoever cut that diamond is expected to do it with the highest precision.

Blunt curves and scratches during the making are sometimes visible to the naked eye, and such shortcomings make the diamond much less valuable.


Did a transparent and colorless diamond come to your mind? 

If so, this is a very rare case. Finding a 100% colorless diamond is pretty rare – and if the opportunity arises, you should grab it by all means. 

As with the previous criteria, there is a scale by which the color of the diamond is graded. The jeweler will evaluate the color by comparing the diamond that was brought to them for an inspection with some of the diamonds they already hold in their collection.

Since a transparent diamond is the most desirable, lab diamonds are generally grown to be as close to colorless as possible.

Yellow and brown diamonds are of the least value, and a colorless diamond is a jackpot!


For many of you, this is the most important category, and you are eager to hear how many carats your engagement ring will have, for example. As with other criteria, the number of carats increases or decreases the value of your diamond.

However, there is one catch: Even if you own a diamond with many carats, if some of the other criteria – color, clarity, and cut – are not in the best shape, the value of your diamond can fall significantly.

Logically, the higher the number of carats, the higher the price, but don’t forget the look and the way the diamond is shaped.

Some people would add confidence as the fifth criteria when buying diamond jewelry.

Whether it is a necklace, a bracelet, or a ring, both the buyer and the seller need to possess a certain amount of self-confidence.

In what sense?

You, as a customer, must clearly express what you want. On the other hand, a well-trained salesperson should be confident in their trading power, and offer you a deal that you will not be able to refuse.

How To Spot A Fake Diamond? 

Many people equate lab-created diamonds with fake diamonds. This is nothing more than prejudice. Lab diamonds are just a type of diamond, while fake diamonds are something completely different.

By definition, a fake diamond is any diamond that is made of different chemical composition. These diamonds are mostly copies made from alternative material.

People will bring fake diamonds to the jewelry store, and there’s no avoiding that. What you can learn, whether you are a professional or not, is how to spot a fake one.

Here are a couple of ways you can do that.

Thermal Test

You need a diamond tester you can buy online. 

You can buy this gadget anywhere on the internet. Once you have ordered your diamond tester from Amazon, you can use it in practice when you want to know if your diamonds / gems are real. The machine works on its own and takes about 30 seconds.You’ll figure out how to use it by reading the instructions.

Learn More: How Much Is A Diamond Tester?

Facet Doubling

You need a jeweler’s loupe.

You’ll examine the diamond closely with a magnifying glass or a loupe. You should be able to see the facets on the back of the diamond. Take your time with this test, and look carefully!

UV Light

You need a UV light or lamp.

UV lights are widely used in trading in order to check the validity of a product. Checking diamonds is very similar. Once you’ve put it under the light, if it shows any color other than the standard blue – it’s a fake!

Learn More: Can Ultraviolet (UV) Light Destroy A Diamond?

Newspaper Test

You need newspapers. (any kind)

Take any newspaper and the gem you are testing. Find a black dot on the newspaper and put a gem face-down on it. If you see the shape of the letters, you have a real diamond with you. If everything is blurry and unclear, you have a fake.

It’s that easy!

Water Test

You need a glass of water.

This is the easiest way to check if a diamond is fake, without damaging it in any way. Put your diamond in a glass of water and pay attention to how it reacts. If it sinks right away, you’ll know it’s real. If it starts floating, it’s definitely a fake.

Markings Test

You will need a magnifying glass and some experience.

Often, markings on diamonds can tell you a lot about their quality and authenticity. For example, if you want to check if your gem is real or fake, you can look for markings on it.

Jeweler’s markings on the diamond often denote how many carats it has, for example. You will see engravings like “10k” or “Ster,” meaning sterling silver.

Some also have a code that you can trace back to the jeweler that initially made it. That’s when you know that the diamond you have is the real deal.

Shatter Test 

You will need water, a lighter, and pliers. 

Attention! This can destroy the gem if it’s fake. People choose to do it only when they are sure that they are not dealing with a real diamond.

You’re going to take the gem and hold it with pliers. The next thing you’re going to do is light a candle or lighter beneath it. You should hold the gem above a light fire for about 40 seconds.

After that, drop the gem into the water. If it shatters – it’s clearly a fake.

You can use protective goggles for the safer handling of the gem.

Read Also: Will A Diamond Shatter If Heated?

Real Vs. Lab-Diamonds

There is no doubt that both real and lab-diamonds are of good quality, but there is still some difference between the two of them. How big is it, and how does it affect your choice?

Let’s break down the differences.


The first and most obvious difference between the two is the price. Over time, the prices of these two diamonds change easily. Until a few years ago, people paid tons of money for lab-created diamonds. But that era came to an end.

Currently, the prices of real mined diamonds have jumped tremendously. This is all due to the fact that the availability of real diamonds is limited.

Learn More: Lab-grown Diamond Price List: Natural Vs. Lab Diamonds Price


The value of a diamond is reflected in its natural and synthetic value, which it will retain for years after it is made and sold. Natural diamonds retain up to 50% of their value, while lab-created diamonds can fall back very easily in this category.

If you want to learn more about lab-created diamonds and their value, click here.


In terms of sustainability, lab-created diamonds have a slight advantage. This type of diamond is environmentally friendly, unlike real mined diamonds, which have a great impact on climate change.

Mining diamonds can be a very unethical job in some cases. So, before you fall for the shine of a real diamond, consider more options. Lab-created diamonds are both economically and environmentally friendly.


To the naked eye, it is unlikely that anyone will be able to tell the difference between a real and a lab-created diamond, unless you tell them. There are some differences in appearance, of course, but if you’re really interested in knowing, you should go to the professional.

The only thing that can distinguish lab-diamonds from natural ones in appearance are small inclusions or blemishes. However, this is difficult to recognize from afar.

Related Read: Are Lab Grown Diamonds Tacky?

Final Words

Now that we’ve come to the end, it’s time to answer the question: can lab-created diamonds pass the diamond tester?

In short, most of them can. Certain types of diamonds, such as carbon lab diamonds will certainly pass the criteria regarding physical appearance, but will have problems with composition.

Today, there are several types of lab-created diamonds, and even more tests on how to check if the diamond that arrived at your jewelry store is fake or real. You can do this even if you have very little experience.

See Also: Is IGI As Good As GIA?