[Rockhounds] Physicists Just Synthesized Crystals Of The Material We Think Is in Earth's Core

[Kreigh Tomaszewski]

Using an anvil made of diamond, physicists have successfully squeezed iron
into the form we think it has deep in the center of Earth.

It's called hexaferrum <https://en.wikipedia.org/wiki/Hexaferrum>, or
epsilon iron (ϵ-Fe), and it's only stable at extremely high pressures.
Scientists think the majority of the iron in Earth's core takes this form,
and a detailed understanding of its properties could help us understand why
the very center of our planet seems to have directional variations in its
texture
<https://www.sciencealert.com/earths-inner-core-isnt-a-smooth-sphere-after-all-its-textured>
–
a property known as anisotropy <https://en.wikipedia.org/wiki/Anisotropy>.

There's just one problem in this quest to understand Earth's core. Here on
the surface, in a nice, relatively low atmospheric pressure regime,
conditions in the core are difficult to replicate. But we can create
high-pressure conditions for brief pulses of time, using diamond anvils and
heat.

"We report here the synthesis of ϵ-Fe single crystals in diamond anvil
cells and subsequent measurement of single-crystal elastic constants of
this phase up to 32 GPa at 300 Kelvin with inelastic X-ray scattering," write
a team led by physicist Agnès Dewaele
<https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.034101> of
the University of Paris-Saclay in France.

https://www.sciencealert.com/physicists-just-synthesized-crystals-of-the-material-we-think-is-in-earths-core