Billietite

Billietite is an uncommon mineral of Uranium that contains Barium.   It has the chemical formula: Ba(UO2)6O4(OH)6•8H2O. It usually occurs as clear yellow  orthorhombic crystals.   
Billietite is named after Valere Louis Billiet (1903–1944), Belgian crystallographer at the University of Ghent, Ghent, Belgium. 

References

External links
webmineral.com

Category:Uranium(VI) minerals
Category:Orthorhombic minerals