How Do Diamonds Crystalize Inside the Earth?

Diamonds are prized for their incredible strength and dazzling brilliance. They’ve been memorialized, celebrated and openly lusted over in music, film, legends and more.

Throughout the course of history, diamonds have undergone quite the evolution in the way they’re mined, cut and worn — particularly as the centerpiece of engagement rings. But there’s not much out there in the public consciousness or creative commons when it comes to the very foundational formation of diamonds beneath the earth’s surface.

Even more fascinating? It now appears that before diamonds can begin to form and crystalize deep, deep down in the planet’s mantle (which begins more than 90 miles below the surface of our planet), they need a bit of a charge from an electric field to get going and growing.

Let’s take a closer look at the science behind the brilliance, shall we?

How it All Begins…

Diamonds are comprised of carbon atoms aligned in a specific crystalline structure. Deep down with the Earth’s mantle, pressures reach several gigapascals (one gigapascal comprises a billion pascals) — and temperatures can skyrocket to as much as 2,732 degrees Fahrenheit. These extreme conditions and intense impacts create carbonate-rich melts that eventually crystallize and evolve into diamonds. Scientists believe that most natural diamonds were formed billions of years ago, with most originating around 125 miles below the earth — but some coming from as deep as 500 miles underground.

However, several details surrounding diamonds’ creation have remained shrouded in mystery over the years. A recent study helped shed some light on just what “kickstarts” diamond formation way, way down there — so very far beneath our feet (and ring fingers).

The Experiment…

The fascinating and illuminating study, since published in Science Advances, involved a team of German and Russian scientists conducting lab-based experiments that approximated conditions inside the mantle. Amazingly enough, their experiments revealed that even a relatively weak electric field of around 1 Volt can help kickstart diamond formation.

To come to these enlightening and electrifying conclusions, the researchers gathered the ingredients required to form a diamond — carbonate and carbonate-silicate powders that approximate those natural carbonate-rich molten melts. They then placed these powders in an artificial mantle in their laboratory, where they subjected them to pressures up to 7.5 gigapascals and temperatures up to 2,912 degrees (talk about Hell’s Kitchen). The kicker? They also exposed the powders to electrode-powered electric fields ranging from 0.4 to 1 Volt in intensity.

After varying periods that lasted up to 40 hours long, diamonds did, in fact, form — along with their softer carbon-based relative, graphite. However, this formation only occurred when the researchers had also set up an electric field of around 1 Volt. Keep in mind, a 1-Volt charge is less than that supplied by most household batteries!

VOILA! Diamonds (Sort of)!

The diamonds and graphite created by these experiments only formed at the cathode, or the negative portion of the electric field. This “hot spot” produces electrons that trigger a chemical process that results in diamond formation.

The synthetic diamonds created in the lab were quite small — featuring diameters no larger than 0.007 inches (around 200 micrometers, or one-fifth of 1 millimeter). Though small in size, they were remarkably similar to naturally-formed diamonds. Both feature an octahedral shape and small amounts of other elements and compounds — including considerable nitrogen content and silicate-carbonate imperfections that are often referred to as “diamond birthmarks.”

What Does It All Mean?

These fascinating experiments strongly suggest that local electrical fields play a vital role in the formation of diamonds deep inside the Earth’s mantle. In the natural world, this local voltage is most likely created by rock melts and fluids within the mantle — with these melts and fluids both featuring a high electrical conductivity. According to a report by Chemistry World, it’s still unclear just how strong these naturally occurring electrical fields are.

Supercharge Your Diamonds with Zillion Insurance

Here at Zillion, we can’t claim the kind of history that belongs to diamonds. But since we first opened our doors, we’ve existed to provide the kind of protection that’s every bit as durable and long-lasting as diamonds (or gold, for that matter).

Backed by our powerful network, wealth of experience, streamlined claims process and overall ease-of-use, we empower each of our customers and clients to enjoy true peace of mind when it comes to your precious jewelry — diamond, gold or otherwise. When your engagement or wedding ring, diamond bracelet or any other insured piece is protected by a Zillion jewelry insurance policy, you won’t feel anything like the kind of pressure – or shock – it takes to form diamonds. And you can walk around feeling safe and secure — right here, far above that scary, pressure-packed, ultra-white-hot molten mantle.

Take charge of your jewelry and start your own personal history with a fast, easy jewelry insurance quote on our homepage today! 


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