CURIENITE

    Class : Phosphates, arsenates, vanadates
    Subclass : Uranyl vanadates
    Crystal system : Orthorhombic
    Chemistry : Pb(UO2)2(VO4)2 5H2O
    Rarity : Very rare

Curienite is an extremely rare vanadate of uranium and lead which is only known exclusively in cryptocrystalline or powdery coatings of lemon yellow color on the crystals of francevillite, a mineral with which it forms a continuous series, the barium then replacing the lead . Its name was given to it in honor of Hubert Curien, French mineralogist and crystallographer at the CNRS and the Mineralogy and Crystallography Laboratory of the Pierre and Marie Curie University (Sorbonne). It is of course highly radioactive and is found in the surface oxidation zones of uranium deposits.


Main photo : Curienite from Mounana Mine, Gabon © Michel Arliguie

Curienite from Mounana Mine, Gabon © Italo Campostrini
Curienite on francevillite from Mounana Mine, Gabon © Alex Earl
Curienite on sabugalite from Rio Giulis, Condino, Trento, Italy © Italo Campostrini
Curienite on fossil bivalves from Akashat Mine, Iraq © Jolyon Ralph

Curienite in the World

Its only notable occurrence is the Mounana uranium deposit (Gabon). However, it is also reported in the uranium veins of Jachymov (Czech Republic), at Akashat Mine (Iraq), at Rote Grube mine and at Burggraben (Germany), in several localities in Trentino (Italy) as well as at Shinkolobwe Mine (Republic Democratic Republic of Congo).

Curienite in France

In France, curienite is reported in Echassières (Allier) as well as in St-Martin-de-Belleville (Savoie).

Twinning

No known twin due to the absence of automorphic crystals but powdery coatings can partially cover fossils, this is the case at the Akashat mine in Iraq.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 3
Density : 4.88
Fracture : Powdery
Streak : Yellow

TP : Translucent
RI : -
Birefringence : -
Optical character : Biaxial -
Pleochroism : None
Fluorescence : None

Solubility : -


Magnetism : None
Radioactivity : Strong