You might think the Earth’s largest gold reserves are locked up at Fort Knox.
But Earth’s core is rich with the precious metal – and it’s slowly making its way up towards us, according to a new study.
Ultra-high precision analysis of volcanic rocks show Earth’s core is ‘leaking’ into rocks above.
And it’s bringing gold and other precious metals with it.
Dr Nils Messling, at Göttingen University’s Department of Geochemistry, said: ‘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.’
More than 99.999 per cent of Earth’s stores of gold lie buried under 2,900km (1,800 miles) of solid rock, locked away within the Earth’s metallic core and far beyond the reaches of humankind.
The team analysed rocks on the island of Hawaii, specifically looking at traces of the precious metal ruthenium (Ru).
Graphic representation of Earth’s shell structure showing the super-heated metallic inner core in the centre, followed by the solid outer core, the rocky mantle and the thin crust towards the surface. New research from the University of Göttingen demonstrates that some precious metal-rich material from the core is leaking into the Earth’s mantle above
Researchers found tiny traces of the precious metal ruthenium with an anomalous isotopic composition in lavas from Hawaii. The new findings prove that the Earth’s core is leaking metallic material, including gold and other precious metals
Compared to the Earth’s rocky mantle, the metallic core contains a slightly higher abundance of a particular isotope called 100Ru.
That’s because this ruthenium, 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 that is contained in the mantle today.
These differences are so small it was impossible to detect them in the past.
Now, new procedures developed by the research team made it possible to analyse them.
The unusually high 100Ru levels they found in lava on the Earth’s surface can only mean that these rocks ultimately originated from the boundary between the Earth’s core and mantle.
Professor Matthias Willbold, who also worked on the study, said: ‘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.’
The findings mean that at least some of the precarious supplies of gold and other precious metals that we currently have access to may have come from the Earth’s core.
Around 99.999 per cent of Earth’s stores of gold and other precious metals are locked away in the Earth’s core, around 3,000 km inside the Earth and far beyond the reaches of humankind
Fort Knox (pictured), officially the United States Bullion Depository, is a secure facility in Kentucky that stores a significant portion of the U.S. government’s gold reserves
It’s believed that when the Earth was forming, gold and other heavier elements sank down into its interior.
As a result, the majority of gold we currently have access to on the Earth’s surface was delivered here by meteors bombarding our planet.
Other elements that could currently be ‘leaking’ out of the core include palladium, rhodium and platinum.
Despite the findings it’s unlikely these precious metals are emerging at a particularly fast rate.
It would also be impossible to drill down to where the Earth’s core begins – approximately 2,900km (1,800 miles) – to access the gold contained down there.
The findings were published in the journal Nature.