Manganese

There are four commercial sources of manganese in the United States, namely, manganese ores, manganiferous iron ores, manganiferous silver ores and manganiferous zinc residuum. The first three are ores; the fourth is a. residual product obtained after roasting zinc from an ore containing zinc, iron and manganese. Although manganese forms a part of over one hundred minerals, and is a relatively widespread element, practically all the manganese in the United States occurring in nature in sufficient quantity to be of commercial value comes from the oxides, mainly psilomelane and pyrolusite. Other oxides are mined, but much less frequently. The carbonate of manganese, rhodochrosite, is not found in sufficient quantities in this country to be of commercial value, but is mined in several foreign countries, as Spain and Wales. The silicate of manganese, rhodonite, contains too much silica to be used for its manganese content, but is sometimes mined for ornamental purposes on account of its beautiful pink color. Other minerals of manganese are too rare to be of commercial importance. 14 p.Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact azgs-info@email.arizona.edu