Never-seen-before mineral found in diamond hauled from deep inside Earth's mantle

In a major discovery, mineralogists identified a never-before-seen mineral in a diamond unearthed from a mine in Africa's Botswana. Little black specks seen in the diamond excavated from deep below the lithosphere, about 410 miles (660 km) below the surface of the earth, has shed light on the planet's unexplored secrets that remain hidden in layers under the terrestrial surface. The diamond has been named after prominent geophysicist Ho-Kwang (Dave) Mao, Live Science reported.

The mineral, named 'davemaoite', is the first-ever example of a high-pressure calcium silicate perovskite (CaSiO3) found on the earth. While another form of the same compound, called wollastonite, is commonly found across the globe, davemaoite is rare and unique. Its uniqueness comes from the crystalline structure that forms only under high pressure and temperatures in Earth's mantle, the mainly solid layer of the planet trapped between the outer crust and inner core, Live Science mentioned.

International Mineralogical Association confirms discovery of 'new mineral'

The never-before-seen mineral was expected to be in large quantities in the earth's mantle owing to its geothermal importance. However, scientists had never directly discovered its evidence as the mineral has a tendency to break down into other minerals as pressure decreases while moving towards the earth's surface. Thus, the sample of the intact davemaoite inside the diamond was confirmed to be a 'new mineral' by the International Mineralogical Association.

"The discovery of davemaoite came as a surprise," Oliver Tschauner, a mineralogist at the University of Nevada Las Vegas and lead author of the study told Live Science.

The davemaoite sample was excavated using synchrotron X-ray diffraction. The technique focuses on a micro-precision high-energy beam of X-rays in certain spots within the diamond. The experts deciphered the content by measuring the angle and intensity of the returning light, Tschauner told Live Science. However, in this case, the quantity of davemaoite inside the diamond was so less (a few micro-centimetres) in size that even powerful sampling techniques could have missed it, he added.

As per Tschauner, davemaoite is an important geothermal mineral found in the earth's mantle. The mineral also contains trace elements, including uranium and thorium, which release heat via radioactive decay. Hence, Tschauner informed, this mineral could also be instrumental in generating a substantial amount of heat in the mantle.

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