VAUXITE
Class : Phosphates, arsenates, vanadates
Subclass : Hydrated phosphates
Crystal system : Triclinic
Chemistry : FeAl2(PO4)2(OH)2 6H2O
Rarity : Very rare
Vauxite is a very rare secondary phosphate known only from two tin quartz veins in Bolivia where it is associated with wavellite and metavauxite. It is derived from the alteration of apatite. It was named in honor of the American mineral collector George Vaux Jr. Vauxite forms beautiful small elongated tabular crystals, gathered in radiate or subparallel aggregates of up to 6 mm, sometimes blue nodules that turn green in the light.
Main photo : Vauxite de Llallagua, Rafael Bustillo Province, Potosí, Bolivia © Y. Okazaki
Vauxite in the World
Twinning
Twinning is known on {010}.
Fakes and treatments
No fakes listed for this mineral species.
Hardness : 3.5
Density : 2.4
Fracture : Undetermined
Streak : White
TP : Transparent
RI : 1.551 to 1.562
Birefringence : 0.011
Optical character : Biaxial +
Pleochroism : Strong
Fluorescence : None
Solubility : -
Magnetism : NoneRadioactivity : None