There are 14 operations that supply 97 pct of the market economy country (mec) manganese and contain nearly all of its resources. Six mines account for about 70 pct of the production and 85 pct of the resources; there are no known resources that are economically close to those that are currently being mined. Costs (January 1989 dollars) of producing manganese concentrates from the operations evaluated are estimated to range from $0.96 To $1.86 Per long ton unit (ltu or 22.4 Lb) of contained manganese. Total mec demonstrated resources evaluated amount to about 1.2 billion tons of in situ ore containing 474 million tons of manganese. Identified resources amount to about 1.8 billion tons of in situ material.