Karl Cäsar von Leonhard


Karl Cäsar von Leonhard was a German mineralogist and geologist. His son, Gustav von Leonhard, was also a mineralogist.
From 1797 he studied at the universities of Marburg and Göttingen, where Johann Friedrich Blumenbach was an important influence to his career. He collected many mineralogical specimens on scientific excursions in Saxony and Thuringia, continued by travel to the Austrian Alps. During his journeys he made the acquaintance of Friedrich Mohs and Karl von Moll. In 1818, through assistance from Baden minister of state Sigismund von Reitzenstein, he was appointed professor of mineralogy at the University of Heidelberg.
In 1807 he founded the popular mineralogical journal "Taschenbuch für die gesammte Mineralogie" — after 1830 the publication was known as "Neues Jahrbuch für Mineralogie, Geologie and Paläontologie".
He was a founding member of the Wetterauischen Gesellschaft. During his career, he maintained correspondence on mineralogical subjects with Leopold von Buch, Johann Wolfgang von Goethe, Abraham Gottlob Werner and Johann Karl Wilhelm Voigt.
In 1824 he introduced the term "loess" into the geological science. Nowadays Leonhard is recognized as one of one of the key pioneers of loess studies The term "leonhardite" bears his name, being defined as a partially dehydrated, opaque laumontite.

Selected works