Abstract
The U.S. Bureau of Mines investigated germanium and gallium extraction from an ore containing 0.089 pct ge and 0.036 pct ga. While previous researchers concluded that a reducing agent, such as so2, is needed to extract germanium and gallium from such ore, this research showed that high extractions (87 pct ge, 97 pct ga) were possible using sulfuric acid alone, if the acid concentration were properly controlled. This control was achieved using a two-stage countercurrent leach circuit. Microprobe analyses revealed that the nonextracted germanium is in solid solution with quartz and therefore cannot be leached with so2 or sulfuric acid.