Diamonds

StarDate: January 10, 2013

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According to Russian scientists, vast beds of diamonds lie beneath the floor of an impact crater in Siberia. Instead of the “girl’s-best-friend” variety, though, they’re industrial grade — good for manufacturing, not so much for ring fingers and earlobes.

In a way, all diamonds are cosmic in origin. They’re made of carbon, which is forged inside stars and expelled into space when the stars die. Earth incorporated carbon from stars that had died long before its birth.

Most of the diamonds on Earth formed far below the surface, where high temperatures and pressures transformed carbon into its crystalline form.

But some diamond formed when large asteroids slammed into our planet, instantly transforming carbon to diamond — carbon that was already here on Earth, or that was in the rock that hit Earth. Tiny diamond grains have been found in the fragments of the asteroid that created Barringer Meteor Crater in Arizona, for example.

The Russian crater formed about 35 million years ago, when an asteroid a few miles in diameter gouged a crater that’s about 60 miles across. The impact could have generated enough energy to create a large bed of diamonds.

In some cases, meteorites arrive with bits of diamond already inside. These small grains may have been created in supernova explosions, when shock waves heated and compressed carbon in the outer layers of the exploding stars — a fiery birth for tiny bits of “ice.”

More about diamonds tomorrow.

 

Script by Damond Benningfield, Copyright 2012

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