Description | Novacekite, Mg(UO2)2(AsO4)2-12H2O, is a straw yellow mineral when it is pure. Part of the magnesium can be replaced by copper, which makes it a mixture of novacekite and zeunerite. In this case, the novacekite is more greenish. Novacekite occurs as secondary uranium mineral in arsenidic hydrothermal veins. |