A promising breakthrough by the fusion energy startup Marathon Fusion suggests that the future of nuclear fusion might not only revolutionize energy production but also bring about a modern-day form of alchemy. According to a report by the Financial Times, Marathon Fusion, based in San Francisco, has proposed an innovative use of its fusion technology to synthesize gold from mercury. The company, in a scientific paper still awaiting peer review, explains how nuclear transmutation—altering the fundamental structure of an atom by removing protons from its nucleus—could enable the transformation of mercury isotopes into gold. Specifically, the process involves converting mercury-198 into mercury-197, which then decays into the stable gold-197 isotope. While this idea sounds like something out of science fiction, it has piqued the interest of experts, including Department of Energy plasma physicist Ahmed Diallo, who called the concept "intriguing" after reviewing the study.
Over the past three years, Marathon Fusion has garnered nearly $10 million through private investment and government grants. The company has primarily focused on developing more efficient fusion power systems, but this new approach adds a commercial dimension to its scientific mission. Achieving fusion—mimicking the intense reactions occurring in the Sun’s core to generate more energy than is consumed—has long been the elusive holy grail of clean energy. Scientists have faced significant challenges in managing the extreme heat and volatility of plasma within intricate reactor environments. Despite progress, fusion remains a technically demanding goal, with only limited success in producing net-positive energy outputs.
However, Marathon Fusion has now broadened its scope by proposing the integration of nuclear transmutation into its reactor design. By introducing specific mercury isotopes alongside conventional fusion fuels such as lithium and hydrogen, the company believes it can create valuable byproducts without disrupting the reactor’s primary energy-generation function. Their model suggests that a fusion reactor with a capacity of one gigawatt could yield approximately 11,000 pounds (or around 5,000 kilograms) of gold annually. Remarkably, this secondary benefit would not interfere with the reactor’s ability to maintain its fuel cycle or reduce its energy efficiency.
Still, some technical caveats persist. Although the gold produced would largely be stable, it could contain small traces of radioactive isotopes. This might require storing the gold safely for 14 to 18 years before it becomes safe to handle or trade. Despite these precautions, Marathon’s leadership remains optimistic. Chief Technology Officer Adam Rutkowski and CEO Kyle Schiller argue that such a dual-purpose fusion facility—generating both electricity and precious materials—could radically reshape the commercial viability of fusion technology. Their techno-economic models show that the gold output could match or even surpass the value of the electricity generated, essentially doubling the plant’s revenue potential.
Furthermore, the implications go beyond gold production. Marathon Fusion emphasizes that similar nuclear processes might be harnessed to create other high-value materials, including rare metals like palladium, isotopes for medical use, and essential components for next-generation technologies such as nuclear batteries. In essence, fusion reactors could evolve into multifaceted production plants, simultaneously solving energy challenges and supplying rare materials to key industries. While the practical execution of these ideas will depend on further research and successful large-scale fusion operations, the vision offered by Marathon Fusion opens up a new frontier in both energy science and economic innovation.
