South African diamond provides new clues on Earth's internal processes

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However, while we have plenty of CaSiO3 supply, it had never been seen by humans in its natural environment.

The rocks can shed light on the deepest parts of Earth's core.

Analysis of the diamond provided rock-hard evidence that material from the oceanic crust-which stretches just six miles below the sea-is recycled into the lower mantle, where the gem was formed.

An earlier study, from December 2016, looked at fragments of some of the world's largest precious stones (the flakes are produced when rough stones are cut and polished) and based on the minerals trapped in them, concluded that they formed at depths corresponding to the deep mantle.

While most of us might value diamonds for their beauty, geologists like the minerals for what they can tell us about the goings on deep within our planet. The perovskite diamond was found less than a kilometer below Earth's surface.

"Nobody has ever managed to keep this mineral [calcium silicate perovskite] stable at the Earth's surface.The only possible way of preserving this mineral at the Earth's surface is when it's trapped in an unyielding container like a diamond", explained Graham Pearson, a researcher and professor at the University of Alberta and one of the study's authors, in the recently published report.

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He quickly followed up to say he got another call from someone advising that "someone was shot in the 1200 Building". It's nowhere near the long-term solution", said Chris Grady, a senior at Marjory Stoneman Douglas High School .

Researchers have estimated that around 93 percent of the Earth's lower mantle is made up of silicate perovskites.

Diamonds are capable of forming deep in the Earth's mantle - sometimes as much as 400 miles beneath the crust. The research team behind the discovery didn't set out to find a new form of ice, but it turns out that at least a few diamonds harbor ice-VII - ice that is around one and a half times as dense as the ice we're used to, and boasting a different crystalline structure in atoms as well. The intense and crushing pressure is believed to have formed the diamond, trapping the rare Earth mineral inside it in the process.

Prevented from crystallizing under high pressure, the water froze as geological activity eventually moved the diamonds to the surface.

"The diamond lattice doesn't relax much, so the volume of the inclusion remains nearly constant whether it's in the Earth's mantle or in your hand", Tschauner said. "It provides fundamental proof of what happens to the fate of oceanic plates as they descend into the depths of the Earth". According to Brandon Specktor of Live Science, the piece of CaSiO3 was visible to the naked eye once the diamond was polished, but an worldwide team of researchers collaborated on analyzing the precious stone with X-ray and spectroscopy tests.

The paper on the perovskite diamond appeared online Wednesday in the journal Nature, under the title "CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle".

It is true that the history of the planet Earth has been only recorded partially.

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