Gold, Silver Suspected Near Japan By MARI YAMAGUCHI .c The Associated Press TOKYO (AP) -- Large sulfide deposits inside underwater volcanoes south of Tokyo could contain vast amounts of gold and silver, Japanese geologists said Friday. About 200 tons of gold and 12,000 tons of silver are believed contained inside the deposits, said Makoto Yuasa, head of marine geology at the Agency of Industrial Science and Technology. A team of agency geologists believe the deposits contain a total of 10 million tons of metals, Yuasa said. He said the deposit's width and thickness are unknown. The probe is part of a government project going on since the 1970s to find undersea deposits. But Yuasa doubted the latest discovery would lead to a Japanese gold rush. ``It's so deep that I would think commercial mining is a bit unrealistic,'' he said. But Yuasa said the deposits were still being formed and were a unique chance for scientists to see the process in action. Similar deposits found on land finished forming millions of years before. Because of the continuing volcanic activity, the site is still spouting hot water -- with temperatures as high as 536 degrees -- from dozens of black chimney-like columns of minerals, Yuasa said. It took the team 10 underwater exploration trips since 1997 to find the deposit after 15 years of observation from boats, Yuasa said. The deposit sits on the eastern rim of Myojin Knoll Caldera in the Pacific, 235 miles south of Tokyo. The caldera, a volcanic crater, is about 4 1/2 miles in diameter and up to one mile deep, he said. He suggested that there might be similar deposits in other previously undetected submarine calderas.