Scientists have found evidence of a watery landscape.
Over 400 miles below the surface, in the Earth's lower mantle, scientists have found evidence of a wet environment.
An very rare gem diamond was found in Botswana's Karowe mine.
It was investigated by scientists from the Gemological Institute of America who were investigating the deep water cycle on Earth.
The jewel was mined from a depth of 410 miles, encasing a piece of the Earth's mantle for safekeeping.
Hydrated minerals such as ringwoodite, enstatite, and ferropericlase were discovered in the diamond during its analysis.