Der Mineraloge (The Mineralogist) by Raphael Ritz, 1883. Thought to depict the Bonn mineralogist Gerhard vom Rath (1830-1888), examining mineral specimens from Lengenbach in a nearby house in Binn, Switzerland
Gerhard vom Rath (20 August 1830 – 23 April 1888), was a German mineralogist, born at Duisburg in Prussia.