Braunstein, Pyrolusite, What Is It in Reality

When systematic chemical experiments became possible in the 18 century, what pyrolusite is became clear. That work resulted in the discovery of several elements. 

The German chemist J. H. Pott made a comprehensive investigation of pyrolusite around 1740 and prepared manganese hydroxide and also some manganese salts. But it was not clear to him that he had an unknown metal in his bottles. He thought that pyrolusite was an aUcaHne earth although similar to alum. This was incorrect, but one very important result came out of Pott s experiments. Pyrolusite is not an iron ore. 

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