Hausmannite is a complex oxide containing both di- manganese. The formula can be represented as Mn2+Mn3+2O4. It belongs to the spinel group crystals. Hausmannite is a brown to black metallic mineral with Mohs hardness of 5.5 and a specific gravity of 4.8.
The type locality is Oehrenstock (Öhrenstock), Ilmenau, Thuringian Forest, Thuringia, Germany , where it was first described in 1813. Locations include Batesville, Arkansas; Langban, Russia High quality samples have been found in South Africa where it is associated with other manganese oxides, pyrolusite and psilomelane and the iron-manganese mineral bixbyite (1827) named it in honour of Johann Friedrich Ludwig Hausmann (1782–1859), Professor of Mineralogy, University of Göttingen, Germany.