Friedrich Mohs

Carl Friedrich Christian Mohs (* 29 January 1773 in Gernrode (Harz); † 29 September 1839 in Agordo, Italy) was a German-Austrian mineralogist.

Mohs studied mathematics, physics and chemistry at the University of Halle (Saale). At the Freiberg Mining Academy he completed his studies with the additional subject of mechanics. One of his teachers in Freiberg was the mineralogist and geognosist Abraham Gottlob Werner, who introduced Mohs to his subjects. In 1801 Mohs became a mine foreman at Neudorf in the Harz Mountains. In 1802 he came to Vienna for the first time to sort and annotate the rock collection of the banker J. F. van der Nüll.

In 1812 Mohs was appointed professor of mineralogy at the Joanneum in Graz. During this time he developed the Mohs hardness scale named after him. With his classification of minerals, which focused primarily on the physical properties (shape, hardness, brittleness, specific gravity) of his objects, Mohs found himself in opposition to most of his colleagues, who placed the emphasis on chemical composition. From 1817 he succeeded his teacher Werner as professor at the Bergakademie Freiberg. Mohs developed at about the same time, but according to his own account independently of Christian Samuel Weiss, a concept of crystal systems, which he published in 1822. In 1826 an appointment to Vienna followed. However, he held his lectures on this subject at the Mineral Cabinet. In 1834, in addition to his professorship, he was also given one of the curatorial posts here. In 1835 Mohs was dismissed from the Mineral Cabinet and as a real Bergrat he was entrusted with the establishment of a Montanistic Museum in Vienna, which he directed from 1835 to 1839. In 1849, this became the Imperial and Royal Geological Survey (today the Federal Geological Survey).

Since 1812 he was a corresponding member of the Prussian Academy of Sciences. In 1822 he was elected a member of the Leopoldina and an honorary fellow of the Royal Society of Edinburgh.

Mohs died in 1839 during a trip to Italy. He was first buried in Agordo, transferred to Vienna in 1865 and buried in the Protestant cemetery in Matzleinsdorf. In 1888 he was transferred to a grave of honour at the Vienna Central Cemetery. In the third district Landstraße in Vienna as well as in the fourth district Lend in Graz the Mohsgasse is named after him. His birthplace Gernrode erected the Mohs Monument in his honour.