The Death of Gold Mining? Mercury Is Being Turned Into Gold

Ancient Alchemists’ Golden Dreams

For millennia, people have been captivated by the idea of transforming “base” metals like lead or mercury into precious gold. This quest began with alchemy, a blend of early chemistry, mysticism, and philosophy dating back to ancient civilizations in China, Egypt, and Greece. Alchemists believed metals matured in the earth – lead was an “immature” metal and gold the perfect final form. If nature could slowly turn lead into gold, they wondered, could human ingenuity speed up the process?

And now it appears like we’ve hit a breakthrough. A startup energy company, called Marathon Fusion, claims to have found a cost-effective way to turn Mercury into pure gold. This is both amazing and scary. It’s amazing because it means mining the earth for gold might soon become obsolete. And it’s scary because it means mining the earth for gold might soon become obsolete. Triggering job loss along with a myriad of other issues, including the price of gold dropping substantially from it’s current record high.

So, let’s take a closer look at what’s actually going on. We’ll start with the recent history, and we’ll go through the process that the startup is going to follow, and cover how much gold could theoretically be generated before addressing the issues that this may or may not have on the mining industry.

In 1902, Ernest Rutherford and Frederick Soddy observed that certain radioactive elements naturally decay into other elements over time, proving that atoms can transform by losing particles. In 1919, Rutherford went further and achieved the first artificial transmutation – he fired high-speed alpha particles (helium nuclei) into nitrogen gas and managed to knock loose protons, turning nitrogen into oxygen. This was a landmark moment: humanity had forced one element to become another, succeeding where alchemists never could. The principle was clear – nuclear reactions, not chemical reactions, were the key to changing elements.

Understanding this requires a simple analogy. If an atom is like a LEGO model, chemical reactions are like rearranging or swapping whole LEGO pieces between models – you can change molecules that way, but you’ll never turn a toy car into a toy spaceship unless you swap out some fundamental pieces. In an atom, those fundamental pieces are protons. Gold remains gold in all chemical reactions because the gold atom always has 79 protons. To make a gold atom out of something else, you’d have to remove or add protons in the nucleus – a far more extreme operation than any chemistry.

It’s essentially nuclear surgery on the atom’s core.

For decades, this was practically unthinkable outside of natural radioactive decay. But with the dawn of the Atomic Age, scientists gained new tools – particle accelerators and nuclear reactors – that could finally snip or swap atomic LEGO pieces and fulfill the old transmutation dream.

Modern Nuclear Transmutation: Making Gold in Labs

By the mid-20th century, scientists knew that, in theory, turning lead into gold was physically possible – it was just a matter of changing three protons (lead-82 to gold-79), or similarly, converting mercury (element 80) into gold (element 79) by removing one proton. The challenge was how to coax nuclei to shed protons (or otherwise change) in a controlled way. The approach would be brute force: slam atoms with subatomic particles at tremendous energies.

In 1980, Nobel-winning chemist Glenn T. Seaborg and colleagues at Lawrence Berkeley Lab famously accomplished a modern alchemical feat: they transmuted a small quantity of bismuth (element 83) into gold. Instead of magical stones, they used the lab’s Bevalac particle accelerator, which hurled charged nuclei (like carbon and neon atoms) to nearly light speed and smashed them into a bismuth target. These violent collisions sometimes knocked out several protons from bismuth atoms, leaving behind atoms of gold. In essence, they blasted bismuth apart and occasionally the pieces reassembled as gold. The transmutation worked – gold atoms were created – but the yield was astonishingly small. Only a few atoms of gold were produced, far too few to see or extract chemically. The team had to detect them by measuring radioactivity from the new gold isotopes as they decayed.

This tiny yield was no accident. Nuclear transmutation is incredibly inefficient and expensive. Most collisions don’t produce gold; many produce other elements or break the atoms into fragments. Seaborg’s experiment ran for many hours at great cost – one co-author estimated it cost “more than one quadrillion dollars per ounce” of gold created when you extrapolate the energy and equipment costs. As another researcher put it, “It is relatively straightforward to convert lead, bismuth or mercury into gold. The problem is the production rate is very, very small and the energy, money, etc. expended will always far exceed the output of gold”. In other words, alchemy by accelerator is a losing economic proposition – a speck of gold might cost a king’s ransom in energy bills.

Fusion Power Meets Alchemy: A New Hope

So why are scientists again talking about turning mercury into gold in 2025? The answer lies in an unexpected synergy between the quest for gold and another long-held human ambition: harnessing nuclear fusion for energy. Fusion is the process that powers the sun and stars – light atoms (like hydrogen) fuse together at extreme temperatures, releasing enormous energy and producing heavier atoms (like helium). For decades, researchers have worked to build fusion reactors on Earth to generate clean energy. A side effect of fusion reactions, especially the fusion being pursued in many designs, is a flood of high-energy neutrons. These neutrons typically slam into a surrounding “blanket” material (often lithium) to breed new fuel and protect the reactor.

Enter a startup company called Marathon Fusion, which recently announced an audacious plan to leverage those spare fusion neutrons for a bit of modern alchemy. In July 2025, Marathon Fusion revealed a proposal to use their fusion reactor not just for energy, but also to transmute mercury into gold. In a preprint research paper, the company outlines how a fusion power plant could effectively serve as an alchemical cauldron – fulfilling the medieval dream while generating electricity at the same time. “Chrysopoeia” (gold-making) has indeed been demonstrated before in labs, they acknowledge, but never in a way that made economic sense. Marathon’s twist is to piggyback gold production onto a fusion reactor, so that both the energy and the gold make the reactor more cost-effective. Essentially, the gold becomes a valuable byproduct of the fusion process, potentially helping fund the expensive development of fusion energy.

How would it work? Marathon’s plan specifically targets mercury-198, a stable isotope of mercury. Their reactor design modifies the typical fusion blanket by introducing a mercury-containing layer (mixed with the usual lithium). When the fusion plasma in the reactor burns, it releases torrents of fast neutrons. In Marathon’s concept, these neutrons would crash into mercury-198 atoms and set off a nuclear reaction called “(n,2n)” – meaning one neutron in, two neutrons out. The effect is that a mercury-198 atom hit by a high-speed neutron can lose a neutron (even as it absorbs the incoming one), transmuting it into mercury-197, an unstable isotope. Mercury-197 can’t hold onto its protons for long – after about 64 hours it undergoes electron capture, a decay process that effectively causes one proton to convert into a neutron. When mercury-197 decays in this way, the atom’s proton count drops from 80 to 79 – it literally becomes gold-197, the one stable isotope of gold. In short, the fusion reactor’s neutron bath knocks a tiny piece off the mercury atoms, and those atoms then “decay” into gold. Alchemists used mystical phrases for this change; modern nuclear engineers might simply call it beta decay. But the result is the same coveted element: Au-197, ordinary gold.

What’s striking is the scale Marathon Fusion claims is achievable. According to their simulations, a full-scale fusion power plant (about 1 gigawatt electric, typical of a large power station) could produce on the order of 2,000 kilograms of gold per year. That’s roughly $352.7 million Australian dollars’ worth of gold produced per year from a single reactor.

Marathon Fusion suggests that selling this byproduct gold could double a fusion plant’s revenue, making fusion energy far more economically attractive. In their words, it could “dramatically enhance the economic viability of fusion energy” and jump-start a fusion-powered electric grid that also churns out gold bars on the side. It’s a bold vision: electricity and gold delivered in tandem, using the most advanced physics to answer an ancient wish.

Now all of this might sound like a golden ticket, but here’s the plot twist: the gold is literally radioactive when its formed and requires 17 years old quote unquote "cool down" time to be sellable. And since the price of gold fluctuates, you can’t really know how much your golden ticket is worth today. And while the concept is rooted in well-understood nuclear physics, it’s important to note that this process exists only in simulations and theoretical designs published in a preprint. No experimental reactor has yet demonstrated gold production at this scale—and, in fact, commercial fusion power itself has not yet been achieved. Until a functioning, sustained fusion plant is built, the gold-making side of this idea remains entirely unproven.

Another practical challenge is the source material. The process specifically requires mercury-198, which makes up only about 10% of naturally occurring mercury. That means large-scale production would require isotope enrichment or separation—technically feasible but costly, energy-intensive, and subject to strict handling regulations due to mercury’s toxicity.

Will this venture kill gold mining globally?

No. At least it won’t for a long time.

Let’s assume everything goes to plan to a tee, which is highly unlikely, but for this scenario to work we’ll roll with it, and it actually generates sellable gold. Two tonnes per gigawatt of thermal power per year is a drop in the bucket compared to the roughly 3,000 tonnes mined annually worldwide. Even if dozens of such reactors were built, the ramp-up would be gradual, giving markets time to adjust. Gold prices are influenced not just by physical supply, but by investor sentiment, central bank reserves, jewellery demand, and its role as a hedge against economic uncertainty. That said, if fusion transmutation ever reached the point of flooding the market with hundreds of tonnes annually, prices could soften, which might squeeze margins for small miners and impact jobs in gold mining regions. In practice, though, the biggest near-term “risk” isn’t to miners—it’s that fusion-generated gold would take nearly two decades to cool down before being sold, making it more of a long-term curiosity than an immediate economic disruptor.

A New Golden Age?

But, with all this being said. The notion of turning lead (or mercury) into gold has travelled a remarkable trajectory, I mean, think about it, from ancient mystics stirring potions in clay crucibles to modern physicists designing cutting-edge fusion reactors. For centuries it was a fanciful metaphor for human transformation and ambition; in the 20th century it became a literal (if costly) laboratory reality; and now in the 21st, it’s being revisited as a practical side-business of fusion energy. There’s a poetic symmetry in this progression. The alchemists sought a Philosopher’s Stone to gain wealth and life. In a way, fusion is a kind of Philosopher’s Stone for our age – a source of virtually limitless energy. If it also happens to spill a bit of gold out of its reaction chamber, all the better.

But of course, extraordinary claims require extraordinary proof. Marathon Fusion’s concept will need to undergo rigorous peer review and, ultimately, real-world testing. Sceptics note that many fusion and transmutation ideas have glimmered with promise only to face setbacks. So all that we can do right now is watch from afar and see what happens.

But the dream that once obsessed emperors and emperors’ magicians is now, with no small sense of irony, being pursued not by robed mystics, but by hoodie-wearing startup founders and lab-coated plasma physicists.