Ramsdellite - Encyclopedia
Class : Oxides and hydroxides
Subclass : Oxides
Crystal system : Orthorhombic
Chemistry : MnO2
Rarity : Uncommon
Ramsdellite is a fairly rare manganese oxide. It is a secondary mineral of deposits containing manganese, which is formed by transformation of one of its polymorphs, pyrolusite (the other being akhtenskite), or groutite. It was named in honor of Lewis Stephen Ramsdell, Professor of Mineralogy at the University of Michigan. Ramsdellite occurs mainly in crusts, in fibrous or lamellar masses, or in steel gray to black crystals which are usually groutite pseudomorph. It is a very accessory ore of manganese.
Main photo : Ramsdellite from Lake Valley, New Mexico, USA © Ronnie Van Dommelen
Ramsdellite in the World
Twinning
No twins known for this mineral species.
Fakes and treatments
No fakes listed for this mineral species.
Hardness : 3
Density : 4.37
Fracture : Undetermined
Streak : Brown-black
TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None
Solubility : -
Magnetism : NoneRadioactivity : None