The experimental results of a leaching process of different manganiferous ores are here reported The leaching treatment showed a satisfactory selectivity of manganese extraction in comparison of other metals such as Al, Si and Na. XRD analyses have been none on the ores before and after the leaching treatment. The experimental results showed a good technical feasibility, of the process which can use alternative feedstocks (containing carbohydrates) to treat different manganese ores. (C) 2000 published by Elsevier Science Ltd. All rights reserved.