Researchers from Shizuoka University and Waseda University have revealed what could be the largest gold deposits in the world, located near Higashi-Aogashima. Using highly sensitive secondary ion mass spectrometry (SIMS), they found that local underwater hydrothermal vents, known as “black smokers,” release what is termed invisible gold from the Earth’s crust.
This unique gold cannot be seen with the naked eye or even under a standard microscope, as it exists in the form of nanoparticles or individual atoms embedded within the structure of pyrite—a mineral often referred to as fool’s gold due to its superficial resemblance to the precious metal.
According to the study’s authors, pyrite from the Higashi-Aogashima caldera currently holds the highest concentration of gold among all known hydrothermal deposits globally. Additionally, the site is situated at a comparatively shallow depth, making it particularly attractive for potential industrial exploitation.
However, the prospects for mining are mired in significant controversy. Active hydrothermal vents host unique marine ecosystems that are home to rare species of crabs, fish, octopuses, sponges, corals, and tube worms. As a result, the international scientific community is urging for the protection of these areas from industrial exploitation.
Currently, there are no commercial underwater gold mines operating worldwide. A previous attempt to establish such a project off the coast of Papua New Guinea failed due to financial difficulties faced by the operating company, coupled with widespread ecological protests that caused substantial damage to the country. Following this, Papua New Guinea instituted a moratorium on new deep-sea mining projects, a decision supported by several other Pacific nations until at least 2030.
Despite this, Japan continues to explore the possibilities of deep-sea resource extraction. The study’s authors believe that the recent findings indicate that the gold reserves near Higashi-Aogashima may be even larger than previously thought.
