Marathon Fusion Says Its Process Could Yield Two Metric Tons of Gold

Marathon Fusion says it has demonstrated a beam-driven fusion process that turns mercury into stable gold, a potential revenue stream for fusion power plants if the technology reaches commercial scale.

The San Francisco startup’s process converts mercury-198 into mercury-197. Mercury-197 has a half-life of about 64 hours and decays into stable gold-197; the system is also designed to breed tritium, a fusion fuel, and generate electricity.

A laboratory simulation models gold production of about two metric tons per year for each gigawatt of thermal capacity. Marathon Fusion says the gold could roughly double a fusion plant’s modeled revenue. The estimate is based on a simulation, not commercial production.

The reported demonstration remains at a small laboratory scale, with output far below commercial levels.

If the technology is commercialized, gold production could reshape gold-market fundamentals, but the reported demonstration does not represent a commercial source of supply.