US startup says nuclear fusion turned mercury into gold in a lab
Marathon Fusion, a startup based in the United States, has asserted that it has successfully converted mercury into stable gold through the application of nuclear fusion technology. The San Francisco-based company announced on Wednesday that it achieved the conversion last month, asserting a production rate 10 times higher than a record established by CERN, the European particle physics laboratory. The company has not provided information regarding its gold production figures or the associated costs of the extraction process.
The company states that it employs neutrons emitted during fusion reactions to bombard mercury. This transforms the mercury into an unstable isotope, a variant of the element that later undergoes decay into gold. The assertion is based on prior experiments conducted at CERN, where scientists utilised the Large Hadron Collider to generate gold nuclei during its operations from 2015 to 2018. CERN reported in 2025 that the experiments had produced approximately 29 picograms of gold, equivalent to 29 trillionths of a gram. The gold nuclei existed for a fleeting moment before being obliterated in collisions with the accelerator’s apparatus.
Marathon Fusion asserts that its process has surpassed CERN’s record by a factor of 10. The claim has elicited parallels with lab-grown diamonds, which have experienced a decline in wholesale prices by 90-95 percent from their 2015 levels, according to a report. The availability of less expensive, laboratory-created stones has exerted downward pressure on the prices of mined diamonds. However, the production of gold via fusion entails distinct challenges. The technology hinges on the advancement of commercial fusion power plants, which have yet to commence electricity sales.
The report indicated that gold produced via this process may contain radioactive isotopes, which could necessitate storage for as long as 18 years before it is deemed safe for commercial utilisation. Marathon Fusion estimates that a future fusion power plant could yield approximately five tonnes of gold each year for every gigawatt of electricity-generating capacity. If 100 such plants were operating, their combined output could reach about 500 tonnes a year, equivalent to roughly 14 per cent of the previous year’s mined gold production, it claimed.
