Karelianite - Encyclopedia
Class : Oxides and hydroxides
Subclass : Oxides
Crystal system : Trigonal
Chemistry : V2O3
Rarity : Very rare
Karelianite is an extremely rare vanadium oxide which has a crystal structure identical to that of corundum. It forms in varied geological conditions : high temperature tactites, primary unoxidized uranium-vanadium ore, vanadiferous bitumens, hydrothermal veins. The associated minerals obviously vary depending on the context : sulphides, graphite, pitchblende, tremolite, etc... Its name comes from its locality of discovery : the Outokumpu schists (Karelia, Finland). It is only known in prismatic grains or acicular aggregates not exceeding 0.5 mm, black in color and very high hardness (8 to 9).
Main photo : Karelianite from St-Andréasberg, Saxony, Germany © R. Hochleitner
Karelianite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 8 to 9
Density : 4.95
Fracture : Conchoidal
Streak : Black
TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None
Solubility : -
Magnetism : NoneRadioactivity : None