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How Diamonds Are Formed

By Michael Fried,

How Diamonds are made in earth and synthetic header

The History of Diamonds

The first diamonds to be unearthed by man were discovered in India in the 4th-century BC and were quickly dispersed along the ancient trade route, the Silk Road. Ancient civilizations believed diamonds were gifts from the Gods and that they would bring health, wealth, and strength.

Since then, we have learned the science of diamond formation, yet we continue to entrust diamonds with similar ideologies.

As the Earth was cooling from its violent cosmic beginnings as a molten planet, intense pressure and heat created the diamonds we continue to extract today. As we journey back in time, you will discover how these precious stones that adorn your finest jewelry were made. Diamonds can be made in multiple ways you may not have known, let’s see how.

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How are Diamonds Made?

100 miles deep in the Earth, a layer separating our hospitable exterior from the molten core, known as the mantle, is where diamonds were made. Temperatures boiled above 2,000 degrees Fahrenheit and pressure exceeded 725,000 pounds per square inch.

The extreme heat and pressure combined actually modified graphite, a crystalline carbon, on the atomic level. This restructured graphite’s molecular composition from a hexagonal sheet pattern into a triangular shape, resulting in diamond.

Lucky for us, nature also has a method of transporting these valuable minerals from deep within the Earth to the surface––volcanic pipes. Deep-source volcanoes start three times as deep as typical volcanoes. The high levels of magnesium and carbon dioxide force the magma to the surface, resulting in a violent eruption. Diamonds are typically elevated through kimberlite pipes, which form a bowl-shaped pockmark in the Earth after eruption. When mining these kimberlite sites, precious and semi-precious gemstones like garnet and peridot are also found among diamonds.

Other Sources of Diamonds

Diamonds are not only formed under the heat and pressure of the Earth’s gravity, but can form in the midst of a collision between Earth and an asteroid. Russia claims to have a deposit of diamonds resulting from a collision 35 Million years ago. Diamonds created during a cosmic collision are not likely to be of gemstone quality. However, they maintain their strength and are likely used for cutting or other industrial purposes. Like the glass that results when lightning strikes sand, the diamonds from asteroid impacts are far from meeting the standards of cut, color, and clarity for your typical engagement ring.

As if truly from the Gods above, meteorites have also been known to deliver diamonds. Since carbon is the fourth most abundant element in the universe, it should come as no surprise that diamonds are not exclusive to Earth. When scientists tracked their first meteorite impact, they were not surprised to find diamonds, but were shocked by the size of the diamonds. The scientists proposed that diamonds of this size could only form within a planet, which could mean these diamonds are from a planet that was destroyed early in our solar system’s history.

Synthetic Diamonds

After learning nature’s process for creating diamonds, the creation of artificial diamonds may have less sparkle, so to speak. The first definitively man-made diamond was created in the General Electric laboratory in 1954.

This first artificial diamond was created through the process of High Pressure High Temperature (HPHT), which tries to replicate nature by superheating and applying force to diamond seeds. Synthetic diamonds are more commonly made using Chemical Vapor Deposition (CVD), which can take 28 days starting with diamond seeds that are superheated in plasma and resulting in a cube-shaped diamond.

Conclusion

We often take for granted how the products we use every day are made and most of these products will become obsolete in mere months. The crown jewel in your engagement ring, necklace, or earrings has probably been taken for granted up to this point, but these indestructible stones will never become obsolete. When purchasing a diamond, whether made by mother nature or man, be sure to consult your Diamond Pro for unbiased reviews of the top diamond retailers globally.

animated guide to diamond formation from earth's crust, carbon crystalline to diamond, volcanic pipe transportation, asteroids, and synthetic man-made diamonds

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Sources

Wikipedia | Volcanic Pipe
The CS Monitor | Russia Awash in Diamonds
National Geographic | How Diamonds are Formed
PBS Crash Course Chemistry | Network Solids and Carbons
Popular Mechanics | How Does an Asteroid Impact Make Diamonds?

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About the author

Michael Fried Michael Fried Mike Fried has over 25 years experience in the diamond industry working with Leo Schachter Diamonds, Moshe Namdar Diamonds, and joining The Diamond Pro in 2007. He is recognized as an industry expert and has been quoted in publications such as Us, People, Page Six, The Next Web and more.
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