A familiar black mineral, an unfamiliar metal

01

Useful before it was understood

Glassmakers already used black manganese ores to alter glass coloration. A useful ingredient, however, was not necessarily an identified element. In 1740 Johann Heinrich Pott showed that the material did not contain the iron that earlier workers had assumed. The familiar mineral had become an analytical problem: what substance gave it its distinctive behavior, and could that substance be separated?

Manganese: history, properties and uses

02

Scheele follows the reactions

Carl Wilhelm Scheele investigated the material then called manganese or black magnesia; in this context the name referred to an ore, not a sample of today’s metal. His 1774 paper described acid reactions and an escaping gas, interpreted through phlogiston theory. Those observations belong to the history of chlorine as well. Scheele’s work helped establish the case for a distinct metallic constituent, but chemical investigation and isolation were different steps.

On Manganese and its Properties (1774), translated excerptsManganese: history and uses

03

Gahn obtains the metal

In 1774 Johan Gottlieb Gahn heated the oxide with charcoal and obtained metallic manganese. In modern terms, this was reduction: oxygen was removed from a compound. The conventional discovery date records that isolation, rather than the first use of manganese-bearing material. Priority remains more complicated than a single date: the Royal Society of Chemistry also records Ignatius Kaim’s earlier report of manganese metal in a 1771 dissertation.

Rediscovery of the Elements: A Historical Sketch of the DiscoveriesManganese: history, properties and uses

What followed

Manganese contributes to steel alloys; its dioxide serves in dry cells and glassmaking. Chemical form matters.

Manganese: history, properties and usesOn Manganese and its Properties (1774), translated excerptsManganese: history and usesRediscovery of the Elements: A Historical Sketch of the Discoveries