Abstract: Non-ferrous metals are recovered from metal bearing ores or other metal sources in substantially quantitative yields by treating a finely divided metal bearing material with an aqueous inorganic acid to form a slurry and baking the slurry at atmospheric pressure and at a temperature of about 350.degree. to 800.degree.C. or higher under quiescent conditions for a period of time sufficient to convert the non-ferrous metals into soluble salts. The fumes from the baking process are scrubbed with a dilute acid solution to extract volatile metal salts. The residue is leached with an appropriate solution or solutions to recover the soluble metal salts which are then recovered from the solution by conventional techniques.