The earth is green beneath your feet

The earth is green beneath your feet.

And not just if you are standing in the grass, or in a puddle of algae.

It is deep, dark green, deep beneath you, in the mantle of the planet.

Peridotite is what they call the stuff. Here, too, there be diamonds. And sometimes, a pretty green gem called Olivine.

Fascinating.

Researchers are now drilling off the coast of Africa, where the peridotite, usually deeply buried beneath other layers of stuff, is mysteriously exposed.

If you find a piece of peridotite for sale in your local rock shop, a chip of the deep earth could be yours to take home.

Or you might find the mineral protruding from the shoulder of some ancient mountain range, such as the American Appalachians, where it was thrust up long ago.

Our planet still holds so many mysteries -- around us, above us and even beneath us.