At first glance, a diamond looks like little more than a small, faceted piece of glass — it’s transparent, it sparkles, and it sits nicely in jewelry. But when you take a closer look, the true value of diamonds grows more apparent. After all, there’s a reason that diamonds are the world’s most beloved gemstone. Want to know some more about what makes diamonds so special? Here are 20 interesting facts you didn’t know about the beautiful diamond.

1. Mined Diamonds Form Deep Underground

It’s no secret that mined diamonds come from underground, but most people aren’t quite aware of how far underground. Diamonds form far below the earth’s outer crust, about 100 miles down in the upper mantle.

To offer a sense of perspective, the deepest hole ever drilled only made it about 7.5 miles (or about 12 kilometers) down. We’d need about 13 such holes to reach prime diamond-making depth.

2. Diamonds Are Pure Carbon

When it comes to making diamonds, the ingredient list is pretty short. In fact, all you need is a single element: carbon. Carbon is an element commonly found on earth and is unique because a single carbon atom forms chemical bonds with up to four other atoms. When these atoms bond with four other carbon atoms tetrahedrally, it forms a rigid, three-dimensional rare crystalline structure of unmatched hardness.

3. Carbon Makes up Both Diamonds and Graphite

Graphite — the slick, dusty material that gives modern pencils their mark-making ability — is also made from crystallized carbon. So why is diamond so different from graphite? The answer is in the structure.

Much like in diamonds, graphite’s carbon atoms bond to four other carbon atoms. But unlike the tetrahedral structure found in diamonds, graphite atoms are arranged more two-dimensionally — layered, like chicken wire. This allows the layers to separate easily, which is something diamond simply doesn’t do.

4. No One Knows How Long It Takes Diamonds to Form in the Ground

Diamonds mined from the ground are extremely old. In fact, some of the oldest diamonds are billions of years old–nearly as old as the earth itself. But the processes involved in creating these diamonds are a bit harder to clock.

It may take billions of years for a diamond to grow deep beneath the earth’s surface, or it may take as little as a matter of hours. At the same time, the processes may not be consistent because environmental conditions could change. A diamond may stop growing for a few million years, and then the process might resume.

5. It Takes a Lot of Heat and Pressure to Make Diamonds

We may not understand how long a diamond takes to form underground, but we have a good idea of how much heat and pressure it takes. To get the process going, you need about 725,000 pounds (328854.5 kilograms) per square inch of pressure, and temperatures of around 2200°F (1200°C). This allows the carbon atoms to bond together correctly, so they don’t end up as crummy old graphite.

6. Explosive Volcanic Eruptions Bring Diamonds to the Surface

For diamonds to travel from the upper mantle to the outer layers of the earth’s crust, they need to hitch a ride with a volcano–but most volcanic vents simply don’t go deep enough. Kimberlite volcanoes, on the other hand, reach far beneath the earth’s surface to the upper mantle.

During kimberlite eruptions, quickly expanding gases push diamonds and surrounding material to the surface. Kimberlite volcanoes are very rare, and scientists believe that the most recent kimberlite volcanic activity may have occurred as far back as 10 to 20 million years ago.

7. Changing Facts: Diamond May Not Be the Hardest Natural Substance After All

According to the Mohs Scale (a way to measure some of earth’s hardest substances), diamonds are the hardest substance in existence. In fact, they’re about four times as hard as the second hardest substance on the scale. However, it looks like the Mohs Scale may be out of date.

Both wurtzite boron nitride and lonsdaleite might be harder than diamond, depending on how you measure it. Scientists think that dying stars pack atoms together so tightly that the resulting “nuclear pasta” makes diamond look like tissue paper. But given that a single gram of nuclear pasta would likely weigh about 1,500,000 tons, you probably wouldn’t have much luck wearing it on your finger.

8. Diamond Color Facts: Not All Diamonds Are Colorless

Although colorless diamonds tend to be the most valuable, diamonds come in a range of colors. These colors include green, blue (like the famous Hope diamond), yellow, brown, orange, purple, red, or even black. The color of a diamond depends on the inclusion of trace elements within the diamond, or the introduction of other imperfections or impurities when it forms.

9. The Word Diamond Derives From a Greek Word

The modern English word diamond has origins in the Greek word adamas, which means “invincible.” This root word is in other similar words, such as adamantine, meaning “unbreakable.” Want even more fun facts about diamonds and the ancient Greeks? They believed diamonds were tears cried by the gods.

10. For a Long Time, Diamonds Were Only Found in India

People have traded diamonds for thousands of years. As far back as the 1st century AD, many ancient cultures thought diamonds to be the most precious stones in the world. So precious, in fact, that ancient Hindus placed diamonds in statues of their gods because they believed diamonds offered protection. But it wasn’t until the 1700s (when India’s diamond supplies started running short) that diamond mines began cropping up in other parts of the world.

11. Most of the World’s Mined Diamonds Come From Only a Handful of Countries

Russia and Botswana are the world’s leading diamond producers, accounting for over half of the world’s annual diamond production. Canada, Angola, and South Africa are responsible for most of the remaining. Together, these five countries produce about 88% of the world’s diamonds. And if we’re talking about the world’s largest diamond market, the United States ranks among the top.

12. Most Mined Diamonds Are Not Used in Jewelry

Thanks to their extreme durability and hardness, diamonds are useful in a range of industrial applications, including cutting, drilling, polishing, etc. And, because a large portion of rough, mined diamonds are unsuitable for jewelry, approximately 80% of mined diamonds become industrial diamonds.

13. The Largest Gem Quality Rough Diamond Ever Found Is the Cullinan Diamond

Found in South Africa in 1905, the Cullinan Diamond weighed a whopping 3,106.75 carats. This natural diamond made its way into the hands of the British Royal Family. It was cut down into nine large diamonds, with two diamonds (the largest of the nine, named Cullinan I and Cullinan II) now holding places of prominence as part of the Crown Jewels.

14. Safety Facts: Traditional Diamond Mining Is Unsafe and Environmentally Damaging

In total, diamond mining results in approximately 1 injury for every 1000 workers annually. At the same time, for every single carat of diamond mined from the ground, around 100 square feet of land is disturbed and nearly 6000 lbs of mineral waste are made.

15. Lab Grown Facts: It Is Possible to Grow a Real Diamond in Controlled Conditions

Lab created diamonds are chemically and structurally the same as mined diamonds. In fact, in 2018 the Federal Trade Commision amended its Jewelry Guides. It got rid of any distinction between lab diamonds and mined diamonds.

16. Lab Grown Facts: The First Lab Created Diamond Was Made in the 1950S

While lab created diamonds are only beginning to change the face of the diamond industry, the first diamond made by man was created nearly 70 years ago. General Electric funded the process, and the resulting diamonds were generally smaller than 0.1 carats and used in their unpolished form for industrial purposes.

17. Lab Grown Diamond Facts: There Are Two Processes Labs Use to Grow Them

To create diamonds in a lab, diamond producers rely on one of two possible methods:  High Pressure-High Temperature (HPHT) or Chemical Vapor Deposition (CVD). HPHT was developed first, but the CVD process is widely considered the superior approach.

High Pressure-High Temperature (HPHT)

HPHT replicates the extreme heat and pressure found within the earth to melt carbon and forces it to bond together. The carbon then crystalizes into a diamond.

Chemical Vapor Deposition (CVD)

CVD takes a slightly different approach. It involves heating a carbon-rich gas to high temperatures until it turns into plasma. This allows the carbon to crystalize and grow around a small diamond starter seed.

18. Lab Grown Diamonds Cost Less and Create Less Waste

While diamond mining can be a hazardous, environmentally unfriendly process, growing diamonds in a lab is ethical and responsible. And, because lab grown diamonds eliminate the long supply chains associated with the mined-diamond trade, they can be sold for significantly less.

A lab grown diamond costs about 20–40% less than a mined diamond of the same quality.

19. Lab Diamonds Grow Very Quickly

While we don’t know how long it takes for natural diamonds to form, we know that growing diamonds in a lab is a fast process. A single carat diamond can grow in around one month.

20. Final Lab Grown Diamond Facts: They Come in All Shapes and Sizes

No matter what kind of diamond you’re looking for, there’s a lab grown answer for you. Click here to browse our collection of the best lab grown diamonds.

Just like diamonds on glass, these 20 facts are only scratching the surface. Want more information on diamonds? We can help you find the best diamond engagement ring. We can also help you find the perfect wedding band or any type of lab created diamond jewelry you want. Contact us today to learn more, we are happy to help!