A quadrillion tons of diamonds lie deep beneath the Earth’s surface

As it turns out, diamonds in the Earth are much more common than we thought. About 1,000 times more common, according to the Massachusetts Institute of Technology.

A new study by an interdisciplinary team of researchers used seismic technology (the same kind used to measure earthquakes) to estimate that a quadrillion tons of diamonds lie deep below the Earth’s surface.

That’s 1,000,000,000,000,000 — or one thousand times more than one trillion.

Don’t expect a massive diamond rush, though.

The deposits sit some 90 to 150 miles below the Earth’s surface, much deeper than current mining machinery allows. The Mir Diamond Mine in Russia, for instance, is the world’s second-largest human-made hole and only goes about a third of a mile deep.

How researchers crunched the numbers

Seismic technology uses sound waves to make measurements, because their speeds change depending on the composition, temperature and density of the rocks and minerals they’re traveling through.

Deep in the earth are cratons, masses of rock shaped like upside-down mountains. They are usually cooler and less dense than surrounding rock and result in faster sound waves.

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But scientists observed that the waves got even faster when moving through the bottom of the cratons, known as their roots.

So they put together virtual rocks, made from potential combinations of materials, and using three-dimensional models, compared the velocities of sound through the variations.

Sound travels through diamond twice as fast as other rocks, so the team of researchers figured there had to be some of the material in the cratons.

“Diamonds are a perfect match because they’re a little bit more dense, but we don’t need a lot of them,” said Ulrich Faul, a researcher in MIT’s Department of Earth, Atmospheric, and Planetary Sciences and a senior participant in the study.

What do you do with one of the world's largest rough diamonds? —

You chip away at it -- for some 47,000 man hours, and then turn it into one lavish neckpiece, featuring 11,551 diamonds.

Diamond in the rough —

The rock, named the Cullinan Heritage, was discovered in 2009 at the Cullinan Diamond Mine in Gauteng Province, South Africa. The mine is where the majority of the world's most famous diamonds have been discovered. The stats? It's a 507.55-carat Type IIA rough diamond, coveted for its extreme clarity and flawless quality.

A cool $35 million —

In 2010, Hong Kong's largest jeweler, Chow Tai Fook, acquired the Cullinan Heritage. The company successfully bid $35.3 million for the 507-carat rock. It's the highest sale price ever achieved for a rough diamond.

A sparkly little family —

Chow Tai Fook cut the Cullinan Heritage into a family of 24 smaller D color, internally flawless diamonds. The process of achieving a technically perfect cut and polish lasted three years.  

Chow Tai Fook collaborated with master jewerly designer Wallace Chan —

In 2014, Chow Tai Fook invited jewelry designer Wallace Chan to unite the diamonds into one single piece of jewelry. "It was a once-in-a-lifetime experience," Chan says of the collaboration.

It's all in the details —

The design process took a team of 22 people and 47,000 hours to make.

Many shapes and sizes —

"It was challenging -- all 24 of the small diamonds came in many different shapes. I had to find a way to achieve optical balance," Wallace recalls. "You'll notice I juxtaposed all the marquise-shaped diamonds on one side and all the pear-shaped diamonds on the other side."

Trial and error —

Chan says many experiments in design were required to create the final piece. One particular 104-carat diamond stood out. "It reminded me of a European church I had visited many years ago. I was attracted by the ceiling of the church because I felt its energy going upwards, almost pulling me up to the dome," recalls Chan. "I felt it again when I saw the petals of the light in the stone -- the infinite reflections of light. It bloomed in my heart like a flower of my dreams. And it inspired the necklace's design." The piece was later named "A Heritage in Bloom."

Defying gravity —

"Gravity was one of the challenges I faced designing the necklace," Chan says. "The necklace would get pulled by the weight of the stones and the structure. I had to fight gravity and find the perfect proportion for each style. It took repeated experiments."

Bling bling bling —

Chan also incorporated hundreds of mutton fat white jade beads and green jadeite, 598 pink diamonds and 10,953 white diamonds, in addition to the 24 main diamonds from the Cullinan Heritage, in the final piece.

Shades of jade —

"The mutton fat white jade beads are like the shape of prayer beads," Chan says. "I think of prayers beads as something that transcends cultures and religions."

Invisible connection —

"I polished the mutton fat white jade beads to perfect roundness, hollowed them out, and placed titanium parts so they could be connected throughout the piece invisibly," Chan explains.

When East meets West —

"I set a diamond inside each bead so the humility and the smoothness of jade - a symbol of the East, embraces the power and sparkles of the diamond - a long celebrated love of the West," Chan says.

Fluttery symbolism —

Chan felt it was important to have strong symbolism running throughout the piece. "I placed butterflies and bats on the necklace. Butterflies stand for everlasting love in Chinese culture, and bats symbolize happiness."

The perfect color combination —

"The green jadeite and pink diamonds are used to bring the piece to life. It took a long time to hand pick the right color and quality of jadeite," Chan recalls.

"A Heritage in Bloom" —

The final piece is uniquely modular and can be worn in 27 different ways. The number is significantly rooted in the Chinese concept of eternity. 27 is the cube of 3, which represents infinity in Chinese culture.

An easy wear —

This is another way to wear the necklace. Chan says the necklace feels almost weightless.

Transforming a masterpiece —

When Chan first began to design the necklace, he didn't think about it being worn 27 different ways. "I had just wanted it to be worn in 5 ways but got carried away. I am happy with the result."

Chow Tai Fook estimates that the market would conservatively value all the finished materials united in "A Heritage in Bloom" at $200 million. The jeweler says it has no immediate plans to sell it.

Trace the journey of one of the world's rarest and largest diamonds

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Faul, who worked in the lab with a team of seismologists, geochemists and other scientists, slightly increased the amounts of diamond in the virtual rocks, until they reached a combination that produced the same advanced speeds they’d been encountering by using seismic technology on the real Earth.

That amount was 1-2% of the craton.

Next, the team multiplied this percentage by the total volume of cratonic roots in the Earth, estimated by thorough mapping of new and old rock formations. They came up with one quadrillion. That’s at least 1,000 times more diamonds than scientists had expected.

How diamonds are formed

Faul said the location of the diamonds at the base of the cratons makes the most sense, as diamonds are formed via extreme pressure and extreme heat, so the weight from all the rock above provides ideal conditions for their formation deep in the Earth’s mantle.

The diamonds that end up in necklaces and rings come closer to Earth’s surface, usually through volcanic eruptions, Faul told CNN.

The study also included researchers from various national and international institutions, including the University of California at Berkeley, Harvard University, the University of Melbourne and the University of Science and Technology of China, among others.