Hope diamond formed stunningly close to Earth's core

[Judi Lynn]

By Rafi Letzter - Staff Writer 3 days ago

New evidence suggests these blue stones originated surprisingly close to Earth's core.

Two of the world's most famous diamonds may have originated super deep below Earth's surface, near the planet's core.

All of Earth's natural diamonds first form deep underground from our perspective on the surface. But from the perspective of this planet's great bulk, their usual births occur relatively far from the core. Zest the Earth like a lemon, and you'd uncover diamonds growing at the bottoms of tectonic plates. Those diamonds form about 90 to 125 miles (150 to 200 kilometers) deep, under pressure that exists just where the crust meets the more fluid outer mantle, or middle layer of the planet. No mines reach that far underground, but some of those diamonds do make their way up to where humans can reach them.

The "Hope" diamond, a large and famous stone, as well as the "Cullinan" diamond, the largest rough gemstone ever found, are different. They're "super deep" stones, new research confirms. A 2018 paper showed that these boron-blue gemstones likely originated somewhere in the planet's hot "mantle," a region between the crust and the liquid outer core of the planet, Live Science previously reported This new research shows that, at least sometimes, the stones form deep in this hot zone.

The research presented today (June 24) at the Goldschmidt geochemistry conference, finds remnants of a mineral called bridgmanite in two less famous diamonds of the same types as the famous gemstones.

More:
https://www.livescience.com/hope-cullinan-diamonds-deep-origins.html

[tblue37]

1. K&R and thanks! nt

[soothsayer]

2. Very cool, I was near the last private home of the Hope diamond yesterday

... sharing stories about it.

Now I can add this!

[NBachers]

3. Now I'm thinking of what kind of gems are produced by the geologic processes on other planets.