Researchers Stumble on First of Its Kind Mineral Deep Inside Earth, Say It Came as a Surprise

A diamond uncovered from the earth's surface around 33 years ago, made researchers come face-to-face with a never-before-seen mineral. The diamond was mined from Botswana and formed directly in the mantle, Live Science reported. It was taken for analysis and experts found a sample of intact davemaoite trapped inside.

The mineral is a high-pressure calcium silicate perovskite which has been theorized by experts but never found in nature, before the find in Botswana. Observations regarding the mineral have been published in Science.

The mineral is a crucial discovery for experts because it gives them an idea about the chemical makeup prevalent in the lower mantle, Smithsonian Magazine reported. Before the discovery in Botswana, researchers had synthesized calcium silicate perovskite in the lab. It was one of the minerals that they speculated was present in that mantle, through their calculations. The team observed that when the formulated mineral was removed from 20 gigapascals of pressure, the composition restructured itself. The elusive mineral was named davemaoite after prominent geophysicist Ho-kwang (Dave) Mao.

Considering the extreme conditions needed for the minerals to remain stable, researchers did not expect to find the mineral in nature. The only way to find it according to researchers, was by digging into the mantle, which was virtually impossible. "The chances, we thought, of finding it were so low that we never really actively looked for it," Oliver Tschauner, a mineralogist at the University of Nevada, explained why there were no active operations in pursuit of such an important mineral.

The impossible happened when the mineral was detected inside the diamond, Smithsonian Magazine reported. Researchers believe that this unique phenomenon took place due to the elusive mineral somehow managing to enter the stone in the mantle.

Diamonds are formed in the mantle and blasted to the earth's crust by volcanic eruption. Davemaoite essentially traveled from mantle to crust, nestled inside the diamond. Experts added that the carbon atoms inside the diamonds have such strong bonds, that it is difficult to change their inside composition. Hence, davemaoite remained unaffected by the pressure and temperature changes that took place outside the stone.

In 2021, researchers observed small black flakes embedded inside the diamond during the analysis, which later turned out to be davemaoite. X-rays and other techniques were used by experts to detect the mineral.

Experts hope that such lucky occurrences keep happening and that more minerals from the mantle appear on the crust, Smithsonian Magazine reported. "The work by Tschauner [and collaborators] inspires hope in the discovery of other difficult high-pressure phases in nature," Yingwei Fe, a geophysicist at the Carnegie Institution for Science said. "Such direct sampling of the inaccessible lower mantle would fill our knowledge gap in chemical composition of the entire mantle of our planet."