Francevillite

Francevillite is a uranyl-group vanadate mineral in the tyuyamunite series. Its chemical formula is (Ba,Pb)(UO₂)₂V₂O₈·5(H₂O). Francevillite is a strongly radioactive mineral. It is typically orange, yellow or brownish yellow. It forms a series with curienite.[1]

Occurrence

Francevillite occurs in the oxidized zone of a lead-bearing uranium–vanadium deposits.[1] Francevillite was first described in 1957 for an occurrence in its type locality of the idle Mounana uranium mine, near Franceville, Haut-Ogooué, Gabon and was named for the city.[2][3]

At its type locality it is associated with curienite (a closely-related uranyl vanadate), chevetite (a lead vanadate), and mounanaite (another lead vanadate). At other localities, francevillite is associated with duttonite, vanuralite, mottramite, carnotite, dewindtite, torbernite, uranopilite, johannite and kasolite.[1]

References

1. ^ a b c d Handbook of Mineralogy
2. ^ a b Mindat.org
3. ^ a b Webmineral data
4. ^ Francevillite at Uranium and Thorium Minerals of the World

List of minerals