Press release: Tapping into the World’s largest gold reserves
No. 85 - 22.05.2025
Ultra-high precision analyses of volcanic rocks show Earth’s core is leaking into rocks above
Earth’s largest gold reserves are not kept inside Fort Knox, the United States Bullion Depository. In fact, they are hidden much deeper in the ground than one would expect. More than 99.999% of Earth’s stores of gold and other precious metals lie buried under 3,000 km of solid rock, locked away within the Earth’s metallic core and far beyond the reaches of humankind. Now, researchers from the University of Göttingen have found traces of the precious metal Ruthenium (Ru) in volcanic rocks on the islands of Hawaii that must ultimately have come from the Earth’s core. The findings were published in Nature.
Compared to the Earth’s rocky mantle, the metallic core contains a slightly higher abundance of a particular Ru isotope: 100Ru. This is because part of the Ru, which was locked in the Earth’s core together with gold and other precious metals when it formed 4.5 billion years ago, came from a different source than the scarce amount of Ru that is contained in the mantle today. These differences in 100Ru are so tiny that it was impossible to detect them in the past. Now, new procedures developed by researchers at the University of Göttingen made it possible to resolve them. The unusually high 100Ru signal they found in lavas on the Earth’s surface can only mean that these rocks ultimately originated from the core-mantle boundary.
Dr Nils Messling, at Göttingen University’s Department of Geochemistry, explains: “When the first results came in, we realised that we had literally struck gold! Our data confirmed that material from the core, including gold and other precious metals, is leaking into the Earth’s mantle above.”
Professor Matthias Willbold, at the same department, adds: “Our findings not only show that the Earth’s core is not as isolated as previously assumed. We can now also prove that huge volumes of super-heated mantle material – several hundreds of quadrillion metric tonnes of rock – originate at the core-mantle boundary and rise to the Earth’s surface to form ocean islands like Hawaii.”
This means that at least some of the precarious supplies of gold and other precious metals that we rely on for their value and importance in so many sectors such as renewable energy, may have come from the Earth’s core. Messling concludes: “Whether these processes that we observe today have also been operating in the past remains to be proven. Our findings open up an entirely new perspective on the evolution of the inner dynamics of our home planet.”
Original publication: Messling N et al. “Ru and W isotope systematics in ocean island basalts reveals core leakage”, Nature 2025. DOI: 10.1038/s41586-025-09003-0.
Contact:
Professor Matthias Willbold
University of Göttingen
Department of Geochemistry and Isotope Geology
37077 Göttingen, Germany