A diamond from Botswana fell into the hands of geologists from the University of Nevada in Las Vegas, in which they found inclusions of a mineral that had not previously been found in natural conditions. Moreover, scientists didn't even hope to find it, since this particular mineral forms at very high temperatures and pressures deep in the Earth's mantle. All attempts to raise the mineral to the surface would result in its disintegration. But it happened and became a small miracle.
Only a diamond can withstand an ascent from depths of 660 km and more. The diamond became a kind of safe, which brought an unexpected find to the surface - calcium silicate (CaSiO 3 ) with a unique cubic crystal lattice. Calcium silicate with other forms of the crystal structure such as wollastonite and brayite are quite common in nature, but the version with the higher (cubic) syngony was obtained only in the laboratory under a pressure of 20 GPa and disappeared as soon as the pressure was removed.
Diamond helped study natural calcium silicate in the laboratory. The inclusions of the mineral, which was named "Davemaoite" after the scientist mineralogist Ho-Kwang "Dave" Mao, were represented by three grains ranging in size from five to ten microns. First, the inclusions were studied using an X-ray machine, and then a hole was drilled in the diamond with a laser and the mineral was evaporated using a mass spectrometer. The device showed a significant presence of potassium in the mineral, a small presence of radioactive elements thorium and uranium.
The discovery of davemaoite makes it possible to clarify the processes occurring in the Earth's mantle. In particular, its connection with radioactive elements and their influence on the heating of the inner layers of our planet. It is expected that deep in the Earth's interior in the lower mantle, from 5% to 7% of deivmaoite occurs in layers or clusters. Now scientists know how and where to find it. This means that new discoveries will follow.
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