Gold Under the Waves
Giant nugget may be world's richest trove
A crater in an undersea volcano near Japan may be the biggest pot of precious metals ever found, holding gold and silver each worth around $2 billion. Its treasure is a 30-acre lump of minerals, as broad as the Pentagon building and 100 feet high, that is still growing as mineral-rich, scalding-hot water spews from a profusion of chimneylike vents.
Finding the monster nugget "is the most exciting thing I've ever been associated with," says volcanologist Richard Fiske of the Smithsonian Institution, who worked with the Japanese-led research team that announced the find in last week's Science. They spotted it through the portholes of a three-person research submarine, the Shinkai 2000, in water 4,000 feet deep in an active volcanic region about 250 miles south of Tokyo. It comes as interest is heating up in deep-sea mining worldwide.
Initial sampling of the Japanese discovery puts the gold content at 20 grams per ton, 40 times the average for typical deposits on land. It may be the largest gold deposit, by tonnage, ever found. To scientists, the excitement comes from proof that many on-land precious metal deposits are remnants of ancient, uplifted volcanoes that exploded beneath the sea. The caldera is in Japan's exclusive economic zone, giving that mineral-poor nation full right to exploit it.
This story appears in the February 22, 1999 print edition of U.S. News & World Report.