BECQUERELITE

    Class : Oxides and hydroxides
    Subclass : Uranyl hydroxides
    Crystal System : Orthorhombic
    Chemistry : Ca(UO2)6O4(OH)6 8H2O
    Rarity : Rare

Becquerelite is a mineral from the oxidation zone of uranium deposits, more rarely uranium pegmatites. It associates with other secondary uranium minerals (studtite, schoepite, fourmarierite) which, like it, results from the meteoric alteration of uraninite. It was described in 1922 on samples from Shinkolobwe (Democratic Republic of Congo), it was named in honor of the French physicist Antoine-Henri Becquerel who discovered radioactivity in 1896. It is a rare mineral which present in small masses or crystals sometimes remarkable, transparent to translucent, of amber yellow color, which can reach 25 mm. These occur as prisms and needles, frequently streaked on {010}, or as tabular individuals. It is a very accessory ore of uranium.

Main photo : Becquerelite from Shinkolobwe, Haut-Katanga, Democratic Republic of Congo © Jean-Marc Johannet

Becquerelite from Shinkolobwe, Democratic Republic of Congo © Gianfranco Ciccolini
Becquerelite from Shinkolobwe, Democratic Republic of Congo © Paul de Bondt
Twinned becquerelite from Happy Jack Mine, Utah, USA © Jason B. Smith
Needles of becquerelite and billietite from Margnac, Haute-Vienne, France © F. Bonnet

Becquerelite in the World

The best known crystals of becquerilte come from the discovery site, the Shinkolobwe mine (Katanga, Democratic Republic of Congo), but becquerelite is also known from many other uranium deposits in the United States, Australia, Canada and in Germany.

Becquerelite in France

In France, the best crystals of becquerelite come from the mines of Margnac II (Haute-Vienne) and Rabejac (Hérault).

Twinning and special crystallizations

Twins are known on {110}, polysynthetic and producing pseudohexagonal aggregates or 6-pointed stars.

Fakes and treatments

No fake or treatment identified for this mineral species.


Hardness : 2.5
Density : 5.1 to 5.2
Fracture : Irregular
Trace : Yellow

TP : Translucent to transparent
RI : 1.725 to 1.830
Birefringence : 0.100
Optical character : Biaxial -
Pleochroism : Visible
Fluorescence : Brown-yellow

Solubility : -

Magnetism : None
Radioactivity : Very strong