Briartite is an opaque iron-grey metallic sulfide mineral, Cu2(Zn,Fe)GeS4 with traces of Ga and Sn, found as inclusions in other germanium-gallium-bearing sulfides.
It was discovered at the Prince LĂ©opold Mine, Kipushi, Shaba, Congo (LĂ©opoldville) in 1965 by Francotte and others, and named for Gaston Briart who had studied formations at Kipushi.
References
Briartite Wikipedia(Text) CC BY-SA