San Francisco-based startup Marathon Fusion has claimed to have converted mercury into stable gold using fusion-generated neutrons, while also reporting progress in isotope enrichment and plans to build a fusion reactor.
In a post on X on October 21, the company said it had demonstrated what it called "high-rate alchemy", claiming its gold-production rate was 10 times the record set by CERN in 2025.
"Last month, we demonstrated high-rate alchemy: turning mercury into real, stable gold, beating CERN’s record by a factor of 10," Marathon Fusion said in the post.
The company also said it had enriched isotopes using what it described as the world’s most powerful plasma centrifuge, surpassing a Soviet record that had stood for 40 years.
"Now, we’re building a fusion reactor in San Francisco to achieve record power density," it said.