Davemaoite
INTRODUCTION:
In 2021, small black specks were found in a diamond in an African mine. It turned out to be a mineral never seen before in nature. It is Davemaoite, known to be an important ingredient of rocks deep underground. It is a mineral that plays a major role in the flow of heat in the lower mantle that extends from 660 to 2700 kilometers below the surface of the earth.
Rare Element Found in the Crust of Earth: Davemaoite.
DISCOVERY:
Its discovery was announced on 11th November by a team led by Oliver Shona of the university of Nevada Shona named the mineral Davemaoite after Hokuang Davemao, a Chinese-American geologist who made many discoveries in high-pressure geochemistry and geophysics. The diamond that contains Davemaoite was extracted from the Orapa diamond mine dug up decades ago. This mine is present in Botswana. George Rossman, a mineralogist sold the diamond that contains specks of Davemaoite at the California Institute of technology. Scientists knew of the possible presence of this mineral in the mantle and that finding a natural sample without drilling miles below the ocean floor was a near-impossible prospect.
“We thought our chances of finding him were so low that we never actively looked for him,” lead author Oliver Tschauner, a mineralogist at the University of Nevada in Las Vegas.
PROPERTIES:
It is a cubic crystal structure. It is one of the three main minerals in Earth’s lower mantle. It makes up 5-7 percent of Earth’s lower mantle.
CHEMICAL COMPOSITION:
Davemaoite is a highly pressurized calcium silicate. Its formula is( CaSiO3) with repeating units. Davemaoite also contains radioactive isotopes uranium, thorium, and potassium. It provides heat due to the radioactive decay of these isotopes of uranium and thorium. It plays a major role in heat flows deep below the Earth’s surface. wollastonite and Breyite are the various forms of calcium silicate present in the crust of the Earth and the middle and lower regions of the mantle. This version can only exist at high pressurize of 20,000 times that found at Earth’s surface. Davemaoite’s presence was revealed by using an X-ray diffraction technique.
EXISTENCE CONDITION:
Davemaoite only exists under high pressure and normally disintegrates if brought to the surface. The specks are embedded within a diamond that ferried it to the surface and keeps it highly pressurized and able to survive intact. The scientists zapped the diamond with X-rays at the advanced photon source of Lambton alloy which revealed that the inclusion was rich in calcium minerals. Scientists verify that it is calcium silicate that is present in different crystalline forms depending on the temperature and pressure at which it is created.
ARTIFICIAL DEVOMAOITE:
Scientists had made highly pressurized calcium silicate Davemaoite in the laboratory and assumed that should exist in the lower mantle. Scientists saw it in geological samples before. Artificially prepared compounds Perovskite have the formula ABX3, where “A” and “B” show cations and “X” represents anion that bonds to both.
SECOND PRESSURIZED MINERAL:
Davemaoite is the second highly pressurized mineral. The first one is the diamond. Davemaoite originated as small black flakes embedded in a diamond mine in Botswana more than 30 years ago. When Tschauner and colleagues began studying the diamond a few years ago, they used x-rays and other techniques to reveal the chemical makeup of the spots. scientists concluded that the mineral is a new mineral for science, occurring at a depth of several hundred kilometers from the upper boundary of the lower mantle.
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