VANURALITE

    Class : Phosphates, arsenates, vanadates
    Subclass : Uranyl vanadates
    Crystal system : Monoclinic
    Chemistry : Al(UO2)2(VO4)2(OH) 11H2O
    Rarity : Very rare

Vanuralite is an extremely rare uranium vanadate. Its name comes from its chemical composition : vanadium, uranium and aluminium. Vanuralite occurs as flattened and lanceolate crystals with perfect cleavage on {001}, but vanuralite occurs mainly as microcrystalline coatings or veneers, lemon yellow to golden yellow, sometimes associated with other vanadates such as curienite or mounanaite.

Main photo : Vanuralite from Mounana Mine, Gabon © Orso Martinelli

Vanuralite from Mounana Mine, Gabon © Jean-Pierre Barral
Vanuralite from Mounana Mine, Gabon © Jean-Pierre Barral
Vanuralite from Mounana Mine, Gabon © Italo Campostrini
Vanuralite from Mounana Mine, Gabon © Stephan Wolfsried

Vanuralite in the World

At Oklo near Franceville and at and at Mounana (Gabon) vanuralite was relatively abundant in microcrystalline incrustations and, exceptionally, in 3 mm crystals grouped in bushes arborescent exceeding 4 cm.

Vanuralite in France

Vanuralite is not present in the French underground.

Twinning

Twinning is known with {001} as the composition plane.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 2
Density : 3.62
Fracture : Undetermined
Streak : Undetermined

TP : Translucent
RI : 1.650 to 1.900
Birefringence : 0.250
Optical character : Biaxial -
Pleochroism : Strong
Fluorescence : None

Solubility : -

Magnetism : NoneRadioactivity : Strong