We are reader-supported. Buying through any red colored link on our site may earn us commissions. Learn More.

How Diamonds Are Formed

By Mike Fried,
jump to animated infographic button

How are Diamonds Made?

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.

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 2,100 degrees Fahrenheit and pressure exceeded 725,000 pounds per square inch — more than 45,000 times greater than at sea level.

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.

According to the Gemological Institute of America (GIA), these diamonds remained hidden within the earth for hundreds of millions of years, out of reach of life on the surface.

To help you with the diamond buying process we lean on our expertise and experience. The author of this article, our CEO, Mike Fried has over 20 years of experience in the diamond industry. Mike started from the bottom, sorting and evaluating hundreds of thousands of diamonds to learn every facet (pun intended) of diamond quality and value. Mike followed that up by spending years buying and selling diamonds on the wholesale market as well as selling tens of millions of dollars worth of diamonds to diamond retailers.

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.

Deal Alert: Get 25% off engagement ring settings at Blue Nile!

Please enter your email address to receive your 25% off coupon code:

(valid until May 6th)

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
Infographic explaining how diamonds are formed

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?

James Allen James Allen is the leader in online diamond sales. Their imaging technology is the same as inspecting a diamond with a jeweler's loupe. They have the largest exclusive loose diamond inventory online and fantastic prices. They also have the nicest collection of lab-created diamonds online.
What we love about them:
  • No questions asked returns within 30 days of shipment. James Allen will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free International Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisals
  • One free resizing within 60 days of purchase
  • Free ring inscriptions
  • Best-in-class high quality imagery of all diamonds in stock
  • 24/7 Customer Service
  • Best-in-class packaging
Arrow down
Arrow up
Blue Nile Blue Nile is the largest and most well-known internet jewelry seller. They have a very large exclusive online inventory. Their high-quality images are catching up to James Allens' and their prices are amazing. Save 25% on settings at [dp-bn-coupon type_id="5" message=" Blue Nile!"]
What we love about them:
  • No questions asked returns within 30 days of shipment. Blue Nile will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisal
  • One free resizing within the first year of purchase
  • High quality images of about half of their diamonds
  • 24/7 Customer Service
  • 100% credit towards future upgrades (must be at least double in value)
  • Best in class fulfillment
Arrow down
Arrow up

Still afraid of getting ripped off?

Before you buy a diamond, get personal buying advice from industry veterans. We'll help you get the best diamond for the money.

Ask your diamond purchase question here

  • Hidden
  • This field is for validation purposes and should be left unchanged.

DISCLAIMER: We don't use your email for marketing. Period.

You Might Like

  • Diamond Prices: A Complete Guide

    A diamonds’ price is determined primarily by the 4 Cs of the diamond. On the wholesale level, diamond prices are first based on a diamond shape and

  • The Best Places to Buy Engagement Rings

    Buying an engagement ring is often one of the first major purchases in a person's life. The process can be fraught with tension as there are so m

  • 1 Carat Diamond Price & Buying Guide

    A wide range of 1 carat diamonds exist both in online markets and local diamond jewelry stores. Not only are there significant differences in beauty

About the author

Mike Fried Mike 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.

Please enter your email address to receive your 25% off coupon code:

Here is your coupon code: GFDSF3GF

Diamond Pro

Diamond Pro

  • Unfortunately, the AI chat we worked so hard training is not helping our readers the way we would like. You deserve the best advice you can get.

    Would you like to contact a human diamond pro? Just fill out this email form and we will answer you ASAP (usually within one day).

  • This field is for validation purposes and should be left unchanged.