VANDENBRANDEITE

    Class : Oxides and hydroxides
    Subclass : Uranyl hydroxides
    Crystal system : Triclinic
    Chemistry : Cu(UO2)(OH)4
    Rarity : Very rare

Vandenbrandeite is an extremely rare hydroxide of copper and uranium. Its existence in the oxidation zones of uranium deposits is conditioned, as for torbernite, by the presence of copper minerals in addition to uraninite. It therefore appears alongside secondary minerals of uranium (kasolite, uranophane, sklodowskite), copper (malachite), and copper and uranium (torbernite, cuprosklodowskite). It was named in honor of the Belgian geologist Pierre Van den Brande, discoverer of the Kalongwe uranium deposit (Democratic Republic of Congo). Vandenbrandeite forms squat, dark green to blackish green lamellar crystals, no larger than one centimeter, grouped in lamellar or fibrous aggregates.

Main photo : Vandenbrandeite from Musonoï Mine, Katanga, DR Congo © Francisco Antonio Garcia Alacid

Vandenbrandeite from Musonoï Mine, Katanga, DR Congo © Jason B. Smith
Vandenbrandeite and cuprosklodowskite from Musonoï, DR Congo © Markus Noller
Vandenbrandeite from Musonoï Mine, Katanga, DR Congo © Stephan Wolfsried
Vandenbrandeite from Musonoï Mine, Katanga, DR Congo © Elmar Lackner

Vandenbrandeite in the World

It is a mineral almost exclusively known in the uranium deposits of Katanga (Democratic Republic of Congo) such as Shinkolobwe, Kambove or Musonoï.

Vandenbrandeite in France

In France, vandenbrandeite has only been described in Rabejac near Lodève (Hérault) in crystals barely millimetric.

Twinning

No twinning known for this mineral species.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 4
Density : 5.03
Fracture : Undetermined
Streak : Green

TP : Translucent to transparent
RI : 1.765 to 1.800
Birefringence : 0.035
Optical character : Biaxial -
Pleochroism : Visible
Fluorescence : None

Solubility : Acids

Magnetism : NoneRadioactivity : Very strong