US3726667A Process of leaching sulfide containing ...
material such as ores, concentrates, and the like containing sulfides of copper, iron, zinc, lead molybdenum, etc., with or without precious metals, are treated with strong sulfuric acid, the concentration being maintained between 80% and 100%. the amount of sulfuric acid is less than 3.8 moles per molar equivalent in the sulfides which react and preferably is 3 moles or less.
