The earth is full of diamonds

Diamonds are the world’s best friend.

And the Earth, it turns out, is a veritable diamond factory.

But pump the brakes on your bobcat, because the diamonds we’re talking about are pretty hard to reach.

Research from Arizona State University published in Geophysical Research Letters suggests that the boundary between the planet’s core and mantle is riddled with diamonds and rust.

Working in the Advanced Photon Source at Argonne National Laboratory, the research team determined this by simulating conditions at the core-mantle boundary.

At this limit, temperatures are more than twice as hot as molten lava – enough to release water from present-day iron minerals to create a rusting effect similar to that which occurs on iron at surface level. .

It is also believed that the reactions between water and these minerals expel the carbon, which puts pressure on the diamond due to the immense forces acting below the surface.

This should excite jewelers everywhere, at least those who own a drill capable of digging almost three thousand kilometers under the earth’s crust.

“It may have lasted billions of years”

The Earth’s mantle is the mostly solid layer of rock immediately beneath the planet’s crust. By comparison, the outer core is a hellish world of liquefied iron and other elements.

One of them is carbon.

The iron-carbon alloy reacted with water under conditions of high pressure and high temperature associated with the deep mantle of the Earth in a diamond anvil cell / Credit: Arizona State University.

The researchers, led by Arizona postdoctoral researcher Byeongkwan Ko, found that laboratory-simulated reactions between iron-carbon alloys and water result in the production of diamonds, at least when the temperature and pressure conditions that exist deep below the Earth’s surface are recreated.

These reactions may also help push carbon further into the mantle, changing previous knowledge of Earth’s carbon composition.

Previously, carbon was believed to be relatively low in the mantle, compared to levels present in the core.

But recreating these carbon processes in the lab may explain that much higher amounts of carbon are introduced into the mantle from the liquid iron below.

It is a process that could have taken place for eons.

“The new discovery of a core-to-mantle carbon transfer mechanism will inform understanding of the carbon cycle in the Earth’s deep interior,” Byeongkwan said.

“It’s even more exciting considering that diamond formation at the core-mantle boundary may have spanned billions of years since subduction began on the planet.”



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Sarah C. Figueiredo