ZIPPEITE mineral bright yellow, orange yellow or yellow golden, yellow green with UV light, of the class sulfates by its radical SO4, of formula: K3 ( UO2 ) 4 ( SO4 ) 2O3 ( OH ) . 3H2O . It is found in the form of flattened crystals, commonly lenticular, rhomboid or slats; in microcrystalline spheroidal crusts or aggregates. It has a matte silky luster. Within the sulfates belongs to the group of ZIPPEITE, mineral discovered in 1845 in the Karlovy Vary Metallic Mountains, in the current Czech Republic. It is named in recognition of Frantiek X. M . Zippe , Austrian mineralogist .