Never-Before-Seen Mineral Found Inside a 'Super Deep' Diamond The find can tell scientists how ocean

[Judi Lynn]

The find can tell scientists how ocean crust is recycled throughout Earth's interior.

By Sarah Gibbens
PUBLISHED MARCH 8, 2018

Hidden inside a diamond forged deep within the belly of the Earth, scientists have found the first evidence of a mineral that's never been seen before.

It's called calcium silicate perovskite, and without a hard casing like diamond, scientists have never been able to keep it stable at Earth's surface.

"We actually had no idea we would find it," said Graham Pearson, a professor at the University of Alberta and co-author on a new Nature paper that details the find.

"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.

More:
https://news.nationalgeographic.com/2018/03/super-deep-diamond-found-calcium-silicate-perovskite-spd/

[eppur_se_muova]

1. Ummm ... calcium silicate contains no carbon atoms, and hence no "carbon bonds".

Diamond, of course, is all carbon. It looks like the journo got things mixed up.

[Judi Lynn]

2. Diamonds reveal sign of the deepest water known inside Earth

A type of ice crystal in gems points to liquid existing up to 800 kilometers below the surface
BY CAROLYN GRAMLING 2:22PM, MARCH 8, 2018

Deep within the hot interior of the planet, ice lurks. Now, a form of super-compact ice, found embedded in diamonds, offers the first direct clue that there is abundant water more than 610 kilometers deep in the mantle.

This ice, identified by its crystal structure and called ice-VII, doesn’t exist at Earth’s surface. It forms only at pressures greater than about 24 gigapascals — corresponding to depths between 610 and 800 kilometers, researchers report March 8 in Science. Its presence in diamonds suggests that there is water-rich fluid in the transition zone between the upper and lower mantle, and even into the top of the lower mantle.

“This is really the first time that we see water at such depths,” says Oded Navon, a mantle petrologist at the Hebrew University of Jerusalem who was not involved in the new study.

When slabs of Earth’s crust sink into the mantle layer below, they drag ocean water with them. How deep the slabs sink has been a long-standing question. Researchers have suspected that abundant aqueous fluid exists in the deep mantle, ferried there by slabs bearing water-rich minerals that shed their water when they reach the transition zone (SN: 7/12/14, p. 9). But scientists have not previously found direct evidence of that water.

More:
https://www.sciencenews.org/article/diamonds-reveal-sign-deepest-water-known-inside-earth?tgt=nr