Wiktionary
francevillite
n. (context mineral English) An orthorhombic-dipyramidal mineral containing barium, hydrogen, lead, oxygen, uranium, and vanadium.
Wikipedia
Francevillite
Francevillite is a uranyl-group vanadate mineral in the tyuyamunite series. Its chemical formula is (Ba,Pb)(UO)VO·5(HO). Francevillite is a strongly radioactive mineral. It is typically orange, yellow or brownish yellow. It forms a series with curienite.