[LargoLasskhyfv]

The first link on their site is alchemy.pdf behind announced a solution. Maybe read that? (40 pages) Or not, because here is the abstract ;)

Abstract A scalable approach for chrysopoeia—the transmutation of base metals into gold—has been pursued for millennia. While there have been small-scale demon- strations in particle accelerators and proposals involving thermal neutron capture, no economically attractive approach has yet been identified. We show a new scalable method to synthesize stable gold (197Au) from the abundant mer- cury isotope 198Hg using (n, 2n) reactions in a specialized neutron multiplier layer of a fusion blanket. Reactions are driven by fast 14 MeV neutrons provided by a deuterium-tritium fusion plasma, which are uniquely capable of enabling the desired reaction pathway at scale. Crucially, the scheme identified here does not negatively impact electricity production, and is also compatible with the challenging tritium breeding requirements of fusion power plant design because (n, 2n) reactions of 198Hg drive both transmutation and neutron multiplication. Using neutronics simulations, we demonstrate a tokamak with a blanket configu- ration that can produce 197Au at a rate of about 2 t/GWth/yr. Implementation of this concept allows fusion power plants to double the revenue generated by the system, dramatically enhancing the economic viability of fusion energy.