Invisible Gold Discovered in Pyrite on Seafloor off Japan

Researchers have detected invisible gold trapped within the crystal structure of pyrite in a submarine volcanic caldera off Japan, with concentrations up to 1.9% by weight — the highest ever recorded in such deposits. Source: infobae

The gold is located in the Higashi-Aogashima Knoll caldera, approximately 350–360 km south of Tokyo, at depths exceeding 700 meters. Source: elconfidencial Unlike visible gold grains, this "invisible" gold is incorporated as a solid solution in the pyrite lattice, often facilitated by the presence of arsenic, lead, and copper. Source: infobae

Key findings

• Samples contained up to 275 ppm gold, with an average of 102 ppm, far exceeding typical deep-sea hydrothermal deposits (0.01–43 ppm). Source: infobae
• The pyrite's gold content was highest in colloform pyrite, formed when superheated fluids meet cold seawater. Source: infobae
• The discovery intensifies debates about underwater mining, as ecosystems around hydrothermal vents host unique species. Source: elconfidencial

While the deposit is relatively accessible compared to other deep-sea sites, commercial extraction remains challenging due to costs and environmental concerns. Source: elconfidencial