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Do Diamonds Absorb Heat?

Do Diamonds Absorb Heat?

Diamonds are not just nice to look at; there is much more to this valuable gemstone than you think. As you already probably know, they’re widely used in the industry, and that’s all thanks to their pretty unique properties.

Have you ever taken a minute to immerse yourself in the subject and think about some of the properties of diamonds? For example, one interesting topic that comes to mind is: Do diamonds absorb heat?

In short, yes. These gems can absorb a lot of heat – and that makes them a multi-practical material. However, this answer barely covers the basics of diamonds and heat. There are many more mind-boggling things you should know about this. 

A little curiosity is a reason enough to scroll down!

Thermal Conductivity Of Diamonds

First off, let’s explain what thermal conductivity is.

By definition, thermal conductivity is the ability of an element to conduct (or transfer) heat. It is expressed in W/(m K), representing the quantity of the heat transmitted.

Important: People often mistake thermal conductivity for thermal conductance. The latter deals with the measure of heat through a particular surface, while thermal conductivity has to do with how well the metal conducts heat within.

Let’s take a look at how well the following solids conduct heat.

SolidsW (m/k)

As you can see, diamonds definitely take the lead here. By looking at this table, you can conclude that diamonds are excellent conductors of heat. Who would’ve thought, huh?

Thermal Conductivity Test: Checking Your Diamond

Thermal conductivity is also associated with diamond testing. By using this feature, you can check whether your diamond is real or fake.

Some people decide to do a DIY check by bringing their lighter closer to the diamond. If there appears to be any damage on the gem’s surface after the flame has been lit, then it is 99% fake. 

Real diamonds can withstand insanely high temperatures. On a related note, diamond testers can help you with this. Do you know how to use one? It’s easy.

Diamond testers are available almost everywhere. You can even buy diamond testers online. Before you switch on your diamond tester, make sure that you clean your diamond well, then turn on the heat-conduction option.

You should point the needle placed on the top at the diamond. After placing it on your gemstone, it will calculate the thermal conductivity and give you the answer to the question of whether your diamond is real or fake. We’ve covered this topic in: Can Diamond Testers Be Fooled?

Specific Heat Capacity

Specific heat capacity is related to how much heat an object can withstand. More precisely, it measures how many kilojoules it takes to change the temperature. It’s expressed in KJ/(kg K). Let’s see how well a diamond performs here:

SolidsKJ/(kg K)
Human body3.47

Diamonds are excellent at absorbing heat because of their strong covalent bond and low phonon scattering. So, let’s talk about that.

Learn More: Why Can Diamond Conduct Heat?

Diamond Covalent Structure

Diamonds are actually giant covalent structures. Each carbon atom in this gem is joined to four other carbon atoms, forming a strong bond. These carbon atoms form a tetrahedral network structure, meaning that they are all connected – and that there are no free electrons floating around.

Take a monocrystalline diamond as an example. It is 99.9% isotope, and it has 12C – the highest thermal conductivity measured.

Low Phonon Scattering

High temperatures include a regular flow of phonons. They travel through the material – and diamonds are characterized by low phonon scattering.

Scattering is a process in which particles that are part of an element scatter. And since the particles in diamonds don’t have a high scattering rate, this essentially saves the diamond from scattering under high room temperatures.

See Also: Do Diamonds Melt Ice?

Melting And Boiling Point Of A Diamond

Here’s an interesting thought for you: If we know that diamonds are used in the metal industry, does that mean they have a melting and boiling point? Yes, of course, they do.

However, diamonds have a high melting and boiling point – again, thanks to their covalent bonds. The atoms that make up the composition of a diamond are so tightly joined together that it takes a lot of heat to separate them.

Let’s take a look at the exact melting and boiling points of a regular diamond.

Melting pointBoiling point
Diamond3550 °C4830 °C

Is that impressive or what? Okay, time for a quick recap:

The melting point refers to the temperature at which a material is converted from a solid to a liquid state, and it generally depends on the pressure and the surrounding environment.

The boiling point refers to the temperature when a material is converted from a liquid state to gas. It’s important to note that the boiling point depends on the environment and the pressure of the material, as well.

Both the melting and boiling point are experiments that you should not be doing without the use of adequate protection. So, if you are sitting at home and thinking about boiling or melting your diamond – don’t.

There is a painless way to find out these facts – and one of them is by reading the rest of this article.

Related Read:

Setting A Diamond On Fire – Myth Or Fact?

It’s not a myth; you can set a diamond on fire. However, this will not happen by lighting up a match. Under high temperatures, your diamond can burn. Impure and fake diamonds will burn even faster than pure ones. 

Why? Because they are mostly just glass copies. Is there a precise burning point for a diamond?

According to experts, the burning point of a diamond is somewhere close to 900 degrees Celsius, along with atmosphere pressure.

A diamond can only burn if you create the right environment – not that you should do that on purpose. Burning occurs when a diamond is exposed to an extremely high temperature, and it is mixed with oxygen.

Here is a short lesson in physics: Carbon and oxygen create carbon monoxide, which generates heat. Your diamond will first start turning red and then white. The carbon monoxide that evaporates from the diamond will cause a fire visible on the surface of your diamond.

Mind you; this is not something you should do at home. That was an example with an emphasis on the diamond. However, it is not the only outcome. The most common example of a diamond burning would be house fires. Gripping housefires are enough to burn down your entire diamond collection and leave you with nothing but ashes.

In addition to house fires, diamonds can burn in lava. What are the chances of that happening? Probably one in a million. The heat of the lava (900°C to 1200°C) is just enough to burn the diamond – but it will not melt it. Yup, that’s right; lava doesn’t melt diamonds.

Diamonds In The Industry

Because of their strength – and the degree of heat they can withstand – diamonds are widely used in many different industries. The most common uses for diamonds are as follows:

  • Diamonds in jewelry
  • Automotive industry
  • Stone polishing and cutting
  • Highway construction and repairs

We told you they’re more than just pretty. Manufacturers use diamonds for cutting purposes. That means that it’s an integral part of the cutting machine. How? It increases accuracy. An excellent example would be the electronics industry, where fine diamonds are embedded on the tops of machines that cut solid metal.

Another everyday use involves drilling. Larger diamonds are part of drilling machines that deal with the exploitation of other minerals, precious stones, and oil. Although you may not be familiar with this, diamonds are used in the production of lenses – as in, they are part of grinding wheels. And after grinding comes polishing. Diamonds can polish plastic, ceramics, solid metals, etc.

Scientists have gone one step further with the use of diamonds in the industry. They started using them for research purposes. Their high thermal conductivity allows them to be part of many experiments and machine parts. For example, one of the common uses of diamonds in laboratories involves heat sinks and X-rays.

Read Also: Do Real Diamonds Show Up On X-ray?

Cubic Zirconia & Moissanite – Can They Burn?

Okay, we are talking about the two most common diamond alternatives here – Cubic Zirconia (CZ) and Moissanite. The question is, can they burn, too? That’s what we’re about to find out.

Firstly, we have Cubic Zirconia. Although this gemstone incredibly resembles a diamond, this is a synthetic version – but it shouldn’t be confused with a lab-made diamond. Mass production of this type of gem began in 1969.

Cubic Zirconia is similar to a diamond, but on the Mohs scale of hardness, it has a rating of 8. Moreover, this stone comes in almost the same colors and sizes as a diamond.

Cubic Zirconia might have the diamond’s looks, but it’s not characterized by high thermal conductivity. That means that Cubic Zirconia can easily ignite and disintegrate when brought into contact with high temperatures.

With Moissanite, there’s a whole different story. This type of gemstone is made of silicon carbide. However, since Moissanite is very rare and not as accessible today, it is mostly made in laboratories.

As far as absorbing heat is concerned, Moissanite is much stronger than Cubic Zirconia and maybe even a diamond. This gemstone tolerates temperatures up to 2730 °C. For Moissanite to burn, you will have to work hard. According to some research, this gemstone can even withstand housefires. Isn’t that incredible?

Related Read:

Insuring Your Jewelry – Should You Do It?

Since you have expensive items such as diamonds in your house or apartment, the first thing you should do is make sure they’re safely stored.

From what you’ve had a chance to read so far, security means storing them in a fireproof place. However, keeping diamonds safe still won’t save them from certain unforeseen circumstances, such as fires or thefts.

For this reason, a majority of people decide to insure their diamonds. Is it a good idea to invest money in this? Well, it depends on the person, but what is certain is that it has more advantages than disadvantages.

Insuring jewelry means that you can get some kind of compensation in case of accidents such as fires. Of course, before you actually buy this insurance policy, you should consult with your insurance agent.

These insurance policies go anywhere from $1,000 to $5,000, so you should really think this through. Here are some useful questions you can prepare:

  • How much does the premium cost?
  • Does the insurance cover a full refund or replacement?
  • Do you need to have your diamonds appraised?
  • Does the insurance policy have to be renewed?
  • What are the exclusions? Which types of damages are not covered?

Important Note: Some insurance policies do not cover jewelry items unless they are mentioned explicitly in the policy.

Read More: Does Insurance Cover A Chipped Diamond?

Final Thoughts

It seems like we’ve mentioned everything there is. That means it’s time to sum things up.

First and foremost, diamonds can absorb heat. That is just one of the many features of these gemstones that makes them a more durable and popular choice of jewelry.

On the thermal conductivity table, diamonds come first with 1000-2500 W/(m K). That can be helpful if you are checking to see if your diamond is real or fake – and it’s usually done with the help of a diamond tester.

Diamonds can withstand great heat, too – but they can also burn. Granted, this happens when the temperature reaches 900 degrees Celsius. They also have their melting and boiling point. 

Cubic Zirconia looks like a diamond but is much less heat tolerant, and it can burn at much lower temperatures. On the other hand, Moissanite is a naturally strong mineral, and some claim that it can even withstand housefires.

To avoid the accident of your jewelry burning in a fire – and the expenses that will follow – the best way to protect it is to insure it.

See Also: Can You Insure A Lab-grown Diamond?