Lava. Ash. Horrifying death. All are known and expected outputs from an active volcano. But one volcano deep in the farthest, frozen reaches of our planet marches to the beat of a slightly different drum. On Ross Island in the Ross Sea, a deep bay in Antarctica, Mount Erebus fumes about 1,350 kilometers (840 miles) from the Geographic South Pole. The world's southernmost active volcano, it bubbles with a permanent lake of blazing lava. And in the gas constantly pouring forth from this gate to the underworld, scientists found microscopic particles of crystalline, elemental gold. According to a 1991 research...