New iron minerals may be primordial water reservoir in Earth's deep mantle

Researchers discovered two iron oxyhydroxides stable at core-mantle boundary pressures, holding up to 15% water by weight. The minerals could explain primordial water storage and dense ultra-low velocity zones above the core.

• Minerals stable at over a million times surface pressure
• Contain up to 15% water by weight
• A five-pound piece would hold a pint of water
• Study published Sept. 8 in Nature Geoscience