Diamond sample containing the hydrous ringwoodite.
The Earth’s transition zone is the part of the Earth that exists between the upper and lower mantle. Scientists often theorize what lies in the transition zone. Many believe that the transition zone contains a lot of water, but there was no proof to support that idea. A group of geologists from the University of Alberta uncovered a water-containing gem that finally confirms this theory: there is water, possibly massive oceans of it, deep beneath the Earth’s surface.