RAMSDELLITE SPECIMENS

Ramsdellite is an orthorhombic manganese dioxide mineral. It is relatively uncommon, and is usually found in deposits containing other manganese oxide crystals. It's named after the American mineralogist, Lewis Stephen Ramsdell. Ramsdellite was one of the new phases he first recognized in the "black manganese oxide" minerals. It was later named in his honour by Michael Fleischer and W. E. Richmond, who fully described the mineral in 1943. The mineral is synonymous with Groutellite.