Abstract: A method of producing copper compounds involves contacting metallic copper with oxygen or an oxygen-containing gas, with an aqueous solution consisting essentially of water in solution in which is a soluble ammonium salt NH.sub.4 X, where X is the anion of the salt, and with ammonia in an amount such that the solution is initially alkaline. As a result of such contact the metallic copper is initially dissolved to form a copper ammine Cu(NH.sub.3).sub.4 X and the formation of the ammine continues until the saturation concentration of the ammine is reached. Subsequently, the ammine continuously breaks down to form 3Cu(OH).sub.2.CuX.sub.2 and the water soluble products of the ammine decomposition continuously reform the amine by further reaction with the metallic copper and the oxygen on oxygen-containing gas.