Early Attempts to Find the Metal in Pyrolusite

Sven Rinman (1720-1792) was a prominent metallurgist in Sweden (section 8.7.2). 

In 1756 he tried to isolate a metal from pyrolusite. He first roasted it and mixed it with charcoal and slag former. After intense heating for 22 minutes he got a small metallic ball. The metal was brittle and looked like bismuth in the fractures. Again, it was not iron A magnet did not attract the metal. Rinman was really on the track of the new metal but did not have time to follow up his discovery. 

In 1774 G. Keim wrote a dissertation De dubis metaUis [About doubtful metals], in which he accounted for reduction experiments with pyrolusite. He wrote I took one part of the powdered pyrolusite and two parts of black flux and melted the mixture at high temperature. On casting the melt I got a regulus, bluish-white and brittle.  

Keim s metal could not be dissolved in pure acids, concentrated or dilute, but could be in a mixture of hydrochloric and nitric acids. No doubt Keim had manganese metal in his crucible. The work on De dubis metallis had, however, been carried out at the University of Trnava in present-day Slovakia and the dissertation attracted very Htde attention. Keim s work has scarcely been even a footnote in the history of the discovery of manganese. 

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