Diamonds from the depths of the Earth contain minerals like never before

In a diamond retrieved from deep below the Earth's surface, scientists have discovered a mineral never seen before and didn't think it existed on Earth.

Named davemaoite after the famous geophysicist Ho-kwang (Dave) Mao, this mineral is the first example of high-pressure calcium silicate (CaSiO 3 ) perovskite found on Earth.

The diamond found deep under the Earth's surface contains an unknown mineral.

Another form of the Casio 3 , called wollastonite , commonly found around the globe, but davemaoite have crystal structure formed only under pressure and high temperatures in the mantle of the Earth , the layer of solid mainly of Left The soil is trapped between the outer core and the crust.

Davemaoite has long been expected to be an abundant and geochemically important mineral in the Earth's mantle. But scientists have never found any direct evidence of its existence because it decomposes into other minerals as it moves towards the surface and the pressure decreases.

However, analysis of a diamond from Botswana, which formed in the mantle about 660 kilometers above Earth's surface, revealed an intact sample of davemaoite trapped inside. As a result, the International Society of Mineralogy has now confirmed davemaoite as a new mineral.

Tschauner and his colleagues discovered the davemaoite pattern using a technique known as synctron X-ray diffraction , which focuses high-energy X-ray beams at certain points inside the diamond with high precision. very small precision. The davemaoite sample inside the diamond is just a few micrometers (millionths of a meter) across, so less efficient sampling techniques will miss it.

Davemaoite is thought to play an important geochemical role in the Earth's mantle. Scientists theorize that the mineral may also contain other trace elements, including uranium and thorium, which release heat through radioactive decay. Therefore, davemaoite can help generate a significant amount of heat in the mantle.

Tschauner said: 'The discovery davemaoite shows that diamond can be formed further in Earth's mantle than previously thought and it shows that we can be the best place to find more new minerals from the mantle.'