Scientists have come up with another detail about the diamond’s formation: the electric fields found deep in the Earth’s crust trigger crystallization. Apart from extreme temperatures and pressures, chemically formed stress gradients from molten rocks may also play a role in diamond formation.
Many natural diamonds formed in the Earth’s crust billions of years ago, deep in the crust. Most come from a depth of 200 kilometers, while some come from 800 kilometers. It crystallizes from elemental carbon by redox reactions in a mixture of partially molten rock in the crust.
Diamonds crystallized with the help of electric fields are conveniently seen as Gray triangles.
But how the diamond formed remains a mystery. A research team in Russia and Germany stressed that electric fields, a previously unthinkable detail, should be considered for the crystallization of the diamond.
When the researchers exposed the artificial mantle melt, a mixture of carbonate-rich minerals, to a pressure of 7.5 GPa and temperatures up to 1600 °C in specially manufactured electrochemical cells, they saw the formation of graphite and diamonds in the cathode with an electric field of only 1 v. Synthesized diamonds exhibit similar characteristics to natural diamonds in terms of octagonal structure and high nitrogen content.
The voltage difference of the high electrical conductivity in the mantle melts and fluids with probably occurs with the movement of other redox reactions may also be present here – we don’t know much about how the electric field. According to the research team’s proposal, the electric field is responsible for reducing carbonates to carbon and triggering the crystallization of diamonds.