Alexander Sadebeck (26 June 1843 in Breslau – 9 December 1879 in Hamburg) was a German geologist and mineralogist. He was a brother of botanist Richard Sadebeck (1839–1905).
He studied mineralogy and geology at the University of Berlin as a pupil of Gustav Rose. In 1865 he received his doctorate with a dissertation on Upper Jurassic formations in Pomerania. In 1872 he was appointed professor of mineralogy and geology at the University of Kiel.[1]
In 1873 he published a new edition of Gustav Rose's Elemente der Krystallographie ("Elements of Crystallography"). He was also editor of the section on geology in Karl Klaus von der Decken's Reisen in Ost-Afrika ("Journeys in East Africa"). Furthermore, he was the author of noted works on tetrahedrite, the crystallization of galena, the crystalline forms of chalcopyrite, etc.[1][2]