History of manganese dioxide

The use of manganese dioxide goes back 17,000 years to the upper Paleolithic period when Stone Age men used it as a pigment for their cave paintings. The Spartans of Ancient Greece used MnO2 in their steel making, thus creating weapons superior to those of their enemies. The Egyptians and the Romans used manganese ore in glass making to give the glass pink, purple and black tints. In the mid-18th century, manganese oxide was a main ingredient in the manufacture of chlorine. In 1816, a German researcher noted that manganese increased the hardness of iron, without compromising its flexibility or strength. In 1868, Georges Leclanché developed the dry-cell battery using manganese dioxide. The battery industry is the second largest consumer of manganese today. The uses for MnO2, like many of the technologies used today in water treatment, have a long and storied history.