Russia Finds Rare Mineral Inside Deep-Earth Diamond

Russian researchers, working alongside international partners, have identified a rare phosphorus-bearing carbonate mineral preserved within a diamond that formed deep in the Earth’s mantle, according to TV BRICS.

The discovery, reported by Russia’s Ministry of Science and Higher Education, marks the first time the mineral bradleyite has been found under such extreme geological conditions.

The bradleyite inclusion, with the formula Na₃Mg(PO₄)(CO₃), was trapped inside the diamond hundreds of kilometers below the surface, where immense pressure and temperature allowed it to form before being carried upward by kimberlite magma.

Its presence provides strong evidence that the deep mantle contains previously unrecognized phosphorus-rich carbonate fluids capable of transforming rocks and contributing to diamond formation.

Carbonate minerals such as calcite and dolomite typically form at low pressures in marine environments and only rarely appear in unusual carbonatite magmas. 

The newly identified bradleyite belongs to a deep-mantle carbonate assemblage containing chlorine-, fluorine- and phosphorus-bearing phases, indicating that volatile and light elements play a far more significant role in deep Earth processes than long assumed.

Researchers also determined the crystal structure of bradleyite for the first time using advanced analytical tools, including electron microscopy, diffraction techniques and 3D structural modelling.

The team believes the finding opens new avenues for understanding the chemistry of the deep mantle and the mechanisms that create diamonds and other rare minerals.