Marathon Fusion targets gold production via nuclear fusion

California-based tech company Marathon Fusion announced its goal to produce gold from mercury using nuclear fusion technology. Their method involves bombarding mercury-198 isotopes with neutrons from a fusion reactor to first convert them into mercury-197, which then decays into stable gold-197.

While theoretically possible through neutron-induced particle decay, the process faces major questions about feasibility, energy efficiency, and cost. Fusion reactors require extremely high neutron fluxes—above 6 million electron volts—to trigger the reaction. Marathon Fusion claims a gigawatt-scale fusion plant could produce several tons of gold annually, but these projections rely on digital simulations of reactors not yet commercially available.

Despite physical possibility, significant scientific and economic hurdles remain. Particle accelerators have only produced minuscule amounts of gold—29 picograms over four years at CERN—making commercial-scale production currently unrealistic. Additionally, the initially radioactive gold would require extensive processing before use.

Although the concept is exciting on paper, the uncommercialized state of fusion technology limits its practical viability. Upcoming compact fusion reactors like the UK's STEP project offer future hope, but for now, Marathon Fusion's plan remains a theoretical curiosity rather than a practical gold rush.