For the first time, scientists have found calcium silicate perovskite (CaSiO3) on the surface of Earth. It may be the fourth most abundant mineral on Earth, but it was one of the rare earth minerals and had never been seen before by human eyes in nature — because above a depth of about 650 kilometres (400 miles), it becomes unstable.
The discovered mineral — called calcium silicate perovskite (CaSiO3)— was found trapped inside a diamond excavated from South Africa’s Cullinan mine (most famous for yielding the world’s largest diamond in 1905, part of which now adorns the crown jewels of the United Kingdom.
“Most scientists would say you would never find it at the Earth’s surface,” he adds. That’s because when the mineral ascends to the surface, less pressure is exerted on it and its carbon bonds are rearranged. Scientists estimate the mineral is the fourth most abundant mineral on Earth, but they have never been able to observe the substance at the surface.
Scientists have estimated that silicate perovskites constitute as much as 93 percent of Earth’s lower mantle, but CaSiO3 had remained hypothetical up until this point. Now that we have our hands on this mineral, scientists will finally be able to study it in more detail.
The diamond it was found inside, just 0.031 millimetres across, is also a super-rare specimen.
The researchers say that the finding provides proof that slabs of oceanic crust that sink deep within the Earth are recycled into the lower mantle.
The mineral composition is CaSiO3, but the article says its carbon bonds become unstable above 650km, that makes no sense. Most likely meant, found at a depth of 650km underground or deeper. The mineral can only exist under ultra high pressure so it will only form if it lives in a little house made of diamond pressing on it. If the diamond get unstable the little house breaks and this mineral doesn't form. So the carbon isn't part of the chemical but the carbon is required to be stable to provide an anvil to press it in.
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