Manganese

The International Manganese Institute
Based in Paris France the IMI is an industry association that represents manganese ore and alloy producers, manufacturers of manganese-based products, traders, industry service providers, companies using manganese to manufacture their products and universities and research organizations world-wide.
Minor Metal Trade Association
Benefits and promotes the interests of its international membership, comprising companies actively involved in all aspects of the international trade of minor metals in all their various forms.
Wikipedia
Encyclopedia definition, information and debate.
Lenntech
Basic physical, chemical and historical information.
United States Geological Survey
Manganese Statistics and Information.
Chemguide
Manganese reations for A-Level Chemistry.
Agency for Toxic Substances and Disease Registry
Manganese Toxicity Information
United States Environmental Protection Agency
Hazard summary for manganese compounds.
Pyrolusite
Manganese Oxide to it's friends information from Amethyst Galleries' Mineral Gallery.
Rhiw.com
Information on manganese mining in Rhiw, Wales with historical photographs and images of the landscape left behind.
Hendrecoed
North Wales Mining Industry website - The manganese mining industry of the former county of Merioneth, North Wales.