URANOSPINITE

    Class : Phosphates, arsenates, vanadates
    Subclass : Uranyl arsenates
    Crystal system : Tetragonal
    Chemistry : Ca(UO2)2(AsO4)2 10H2O
    Rarity : Rare

Uranospinite is a rare arsenate of uranium and calcium. It is a secondary mineral of the surface alteration zone of uranium deposits, where it mainly accompanies metazeunerite. Its name comes from its chemical composition and from the Greek spinos (spark), in allusion to its color. Uranospinite forms small rectangular lamellae barely millimeters, often gathered in aggregates, of light green to green-yellow color.

Main photo : Epitaxial uranospinite on green zeunerite from Montoso quarries, Piedmont, Italy © Pasquale Antonazzo

Epitaxial uranospinite on green zeunerite from Montoso, Piedmont, Italy © Beppe Finello
Uranospinite from Montoso quarries, Piedmont, Italy © Pasquale Antonazzo
Uranospinite and uranophane from Mas d'Alary, Hérault, France © Frédéric Bonnet
Uranospinite from Rabejac, Hérault, France © Stephan Wolfsried

Uranospinite in the World

Uranospathite is known in many polymetallic and uranium veins in the Black Forest (Germany), in deposits in South Australia (Radium Hill, Myponga) and the Colorado Plateau. Beautiful epitaxial crystals on zeunerite are reported at the Montoso quarry in the Italian Piedmont.

Uranospinite in France

In France, uranospinite is reported in the Rabejac deposit near Lodève (Hérault).

Twinning

No known twins for this mineral species.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 2 to 3
Density : 3.45
Fracture : Micaceous
Streak : Pale yellow

TP : Translucent
RI : 1.550 to 1.587
Birefringence : 0.022 to 0.027
Optical character : Uniaxial -
Pleochroism : Visible
Fluorescence : Yellow

Solubility : -

Magnetism : NoneRadioactivity : Strong