Green roubaultite and yellow kamotoite. From: Kamoto East Open Cut, Kamoto, Kolwezi, Lualaba, DR Congo. — Photo: David Hospital · CC BY-SA 4.0
Roubaultite
Roubaultite is an IMA-recognized mineral species in the carbonate class, with the chemical formula Cu₂O₂(UO₂)₃(CO₃)₂(OH)₂·4H₂O.
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 3; specific gravity 4.71; Vitreous to slightly greasy luster; optically biaxial.
IMA symbol Rbl, IMA status: approved, named in 1970.
A rare mineral found in the zone of oxidation of copper-bearing uranium deposits, produced through alteration of uraninite.
It is found associated with Vandenbrandeite, soddyite, becquerelite, cuprosklodowskite, uranophane, heterogenite, uraninite (Shinkolobwe, Congo).
The mineral was named to honor Marcel Edouard Roubault (1905–1974), Professor of Geology, University of Nancy, Nancy, France.