Researchers discovered  the first-ever sample of a water-rich gem that suggests there is vast amounts of water stored in the center of the Earth.

The mineral, called  ringwoodite, contains a heavy 1.5 percent of its weight in water, this suggests the layer between the Earth's upper and lower mantle is water-rich, a University of Alberta news release reported.

"This sample really provides extremely strong confirmation that there are local wet spots deep in the Earth in this area," Graham Pearson, Canada Excellence Research Chair in Arctic Resources at the U of A, a professor in the Faculty of Science, said in the news release. "That particular zone in the Earth, the transition zone, might have as much water as all the world's oceans put together."

The mineral is a form of peridot, and is believed to come from high pressure regions of the Earth's transition zone. Ringwoodite has been found in meteorites in the past, but this finding marks the first-ever terrestrial sample. 

The sample was discovered in Brazil in 2008, but came into the researchers hands "almost accidentally."  The team was looking for a different mineral when they came across a "three-[millimeter]-wide, dirty-looking, commercially worthless brown diamond," the news release reported. The ringwoodite was found buried beneath the diamond's surface. 

""It's so small, this inclusion, it's extremely difficult to find, never mind work on," Pearson said, "so it was a bit of a piece of luck, this discovery, as are many scientific discoveries."

The researchers used infrared spectroscopy and X-ray diffraction to determine the identity of the mineral. 

Researchers are unsure about the properties of the Earth's transition zone; the discovery that this layer is full of water could help scientists gain insight into plate tectonics. 

"One of the reasons the Earth is such a dynamic planet is the presence of some water in its interior," Pearson said. "Water changes everything about the way a planet works."