Diamonds are precious stones that are often referred to as the ultimate symbol of love and wealth.

Ever thought what are they made of?

They are essentially made up of carbon atoms that are rigidly fixed together making them robust and extremely long lasting and durable.

There are three essential ingredients that are necessary for diamond formation: Heat, pressure and time.

Without these ingredients, diamonds would not exist. Therefore, these components need to be considered when explaining what diamonds are made of.

Heat, Time and Pressure

Diamonds began formation within the Earth’s mantle more than a billion years ago.

The heat and pressure form the diamond and they travel to the surface of the Earth when the volcanoes erupt.

They also move to the Earth’s surface when Earth plates shift naturally. Diamonds are also formed with the intense heat and pressure of asteroid strikes.

In order for diamonds to thrive they need a very hot temperature. A minimum of 752°F (400°C) is needed.

The best environment for optimum diamond formation is approximately 160 km below the ground.

How are Colored Diamonds Made?

A lot of people love to buy diamonds that are fancy colors.

Clear colorless diamonds are the most popular and well known diamonds in the world, however, diamonds actually come in a myriad of colors such as black, blue and purple.

These colors are formed as a result of mineral defilement or lattice destruction:

Purple diamonds are formed as a result of plastic contamination.

Black diamonds are formed as a result of graphite formation.

Blue diamonds are formed as a result of nitrogen contamination.

What About Lab-Grown Diamonds?

As a result of the astronomical cost of naturally formed diamonds geologists introduced specific ways to create robust diamonds in the lab.

It is believed that lab-grown diamonds were initially introduced in the 1950s by Swedish and American geologists and researchers, they discovered that it’s possible to create diamonds by converting graphite and molten iron.

Lab diamonds are not natural “oh really? ” but they use a very similar process to create the diamonds.

They take advantage of high temperatures, pressure and carbon.

Lab diamonds look no different to naturally formed diamonds and they are significantly cheaper making them a very popular choice in recent years, we’re talking about 30-40% cheaper compared to earth-mined diamonds.

They are formed by utilizing natural or laboratory formed diamond seeds . Scientists use diamond seeds to make exact replicas of real, naturally formed diamonds.

Then comes using the heat, pressure and chemical vapor deposition to make the diamond, the interesting part is that lab diamonds are formed very quickly (matter of weeks), compared to billion years for an earth-mined diamond.

This is one of the major advantages of this type of diamond, resulting in more supply in the market as needed, without having a single company controlling the whole global diamonds market (did I hear someone saying De Beers?)

Because lab diamonds are not grown in labs, they are all produced ethically, as opposed to many of the natural diamonds on the market that might be part of a conflict (rare, but they are still there).

Both types of diamond utilize the same source: Carbon, heat, pressure and time, however, one is formed in the lab and one is formed naturally over billions of years.

How Are Diamonds Formed

There have been several studies done on old diamonds and results show that there is strong evidence that these diamond were formed long before there was any vegetation on the planet. This happened during the pre Cambrian period before there was any plant life on earth. Diamonds are also found about 150 kilometers below the earth’s surface while coal normally forms at only 4 kilometer below the earth’s surface.

Several theories explain the ‘how are diamonds formed’ phenomenon. They are thought to have aided in formation of natural diamonds.

1. Formation in the Earth’s Mantle

The earth’s mantle and is found about 150 kilometers below the earth’s crust . Here, temperature are about 1200 degrees Fahrenheit or 1050 degrees Celsius. There are also very high pressures and the combination of those two aspects is very conducive for diamond formation from carbon rock.

After formation, the diamonds are brought into the earths surface by deep volcanic eruptions. This form of diamond formation provides most of the global commercial diamonds. It is good to note that this temperature and pressure combination can only be found of selected places world wide.

2. Formation on Subduction Zones

When a tectonic plate is forced deep in to the earth’s surface, diamonds are formed when it is brought back up, as the plate is goes deep in to the surface, great pressure is created.

This form of diamond formation can occur as low as 60 kilometers below the earths surface and only a temperature of about 390 Fahrenheit (200 Celsius) is needed. This form of tectonic movement happens to oceanic plates because they are easy to subdue due to their high density.

This explains why diamonds found in Brazil have properties of oceanic crust. Diamonds formed this way are however very tiny and are not used for commercial purposes.

3. Asteroid Influence

When asteroids fall on the earth, a great crater is created on impact. When this happens, a combination of great pressure and temperature is created. The pressure is further accelerated by the speed in which the asteroid travels.

The energy created is similar to several nuclear weapons and the temperature is hotter than the sun’s surface. The place of impact has to have a carbon rock though to enable diamond creation.

This is the reason why asteroids have been falling for millions of years and diamonds have only been found in a few locations.

4. Diamonds From Space

A large number of nano-diamonds were found when cutting through the Allen meteorite. As meteorites travel through space, they are prone to collisions amongst themselves and other objects and this produces great pressure.

Meteorites also contain carbon and the heat that meteorites carry if also high thereby creating an excellent atmosphere for diamonds to form. Diamonds of this nature are however not suitable for commercial use and are used as source of diamond material.


To conclude, diamonds are made from carbon atoms that form as a result of heat, pressure and time.

They are formed over billions of years and they come to the Earth’s surfaces when volcanoes erupt or when the Earth’s plates move naturally.

Lab diamonds essentially look exactly like naturally formed diamonds however, they are formed in a laboratory instead of by the natural process of time, heat and pressure.

Diamonds are the most rare, beautiful and magical stone there is on earth.

Now your question on ‘how are diamonds formed & made of’ is less ambiguous and you now know where your gorgeous stone might have originated from.

Now learn more how to buy diamonds correctly.

About the author

Olivia Bennett is a dynamic and accomplished expert in the diamond industry. With over a decade of experience, she has established herself as a go-to authority for all things diamonds. Olivia's love affair with these exquisite gemstones began in her childhood and has only grown stronger over the years.

Having worked closely with diamond miners, manufacturers, and retailers, Olivia possesses a comprehensive understanding of every aspect of the industry. From diamond grading to sourcing and the latest design trends, her expertise is unparalleled. Clients value her impeccable taste, attention to detail, and personalized approach.

Driven by a passion for education and empowerment, Olivia launched her own website dedicated to diamonds. Through engaging and informative content, she guides individuals through the intricacies of diamond buying, helping them make confident and informed decisions.

Olivia's mission is to ensure that everyone finds their perfect diamond, one that truly reflects their unique desires. With her extensive knowledge and unwavering dedication, Olivia is a trusted guide in the dazzling world of diamonds.