Materials are exposed to the extreme pressures of the Earth’s crust and mantle pressing down on them at the mantle-core barrier. Even temperatures of 4,000 °C (7,232 °F) have effects. It has been discovered via research into how common materials behave at certain depths that the boundary both produces an abundance of diamonds and oxidizes the iron to rust.
Joan Baez sings, “We both know what memories may bring, they bring diamonds and rust. “The ability of memories to transform charcoal into priceless gemstones and gleaming metal into useless oxides may be well known, but what occurs 1,864 miles (3,005 kilometers) below the Earth’s surface is less well known. However, a publication in Geophysical Research Letters claims that the forces present there give the metaphor of physical reality.
Dr. Byeongkwan Ko, then a candidate at Arizona State University, recreated these forces (although on a very small scale) and applied them to the iron-carbon alloy (Fe3C) and water using the Advanced Photon Source at Argonne National Laboratory.
Despite the stark changes in atmospheric pressure, they discovered that the interaction results in the production of rust-like iron oxides and iron hydroxides. These pressures also force the alloy’s carbon out, converting it to diamonds in the process.
According to senior author Professor Dan Shim, “temperature at the boundary between the silicate mantle and the metallic core at 3,000 km depth gets to about 7,000 °F, which is sufficiently hot for most minerals to lose H2O trapped in their atomic size structures.” In fact, the temperature is so great that under these circumstances some minerals should melt.
It is believed that the iron-rich core would include a sizable amount of carbon due to the strong bond that carbon has with iron. Additionally, a startling amount of carbon has been detected in the mantle, which scientists had previously been unable to explain.
According to the scientists, whenever hydrogen is abundant close to the core-mantle border, it alloys with the liquid iron in the outer core and drives out other light elements, such as carbon. Their research suggests that as carbon leaves the core and reaches the mantle, it transforms into diamonds.
Since the start of subduction on the planet, diamond creation at the core-mantle interface may have been ongoing for billions of years. said Ko. Near the border, a sizable portion of the carbon on Earth may be present in diamond form.
One of such minerals that can form through a variety of processes under various circumstances is diamond. These ones are safely out of the miners’ reach. However, the authors believe that their existence could shed light on the riddle of carbon in the mantle. Additionally, they are hopeful that research into seismic wave velocity would confirm their findings.
Shim explained that since diamond is incredibly incompressible and less dense than other materials at the core-mantle barrier, seismic waves should go through diamond-rich formations at the core-mantle border extraordinarily quickly.
The authors are hoping to replicate this work and add to our understanding of the deep mantle’s composition by examining how other prevalent elements behave under similar circumstances.
Science may support Baez’s words, but her contemporaries in songwriting don’t fare as well. Whether Lucy is present or not, it appears that the diamonds are located well below our feet, where, despite popular belief, rust does really sleep.