Demesmaekerite

Demesmaekerite is a rare uranium mineral with the chemical formula: Pb2Cu5(UO2)2(SeO3)6(OH)6·2H2O.

It is named after the Belgian mineralogist Gaston Demesmaeker, who worked at the Musonoi Mine in Katanga It is a secondary mineral which contains lead, copper and selenium, it is a bottle green to brown/yellow color, its crystal habit varies depending on where it is found.

It can be found associated with other rare selenium-bearing uranium ores, such as haynesite , marthozite