In contrast to the western part of the Lower Silesia, information about the basalt-derived weathering crusts occurring in the Opole region is rather limited. However, in 2018, significant volumes of such regolith (about 20,000 m3) were discovered during development works in the NW part of the Rutki Quarry near Niemodlin. This weathering crust is rich in clay minerals and represents a smectite- kaolinite mixture with some halloysite, the latter being a poorly ordered member of the kaolinite group. The minerals of the smectite group contain in their interlayer spaces bivalent cations (calcium and magnesium), which is the most often case in the nature. The mineral composition of the regolith mass is supplemented by iron-containing phases, i.e. goethite and magnetite, and traces of phosphate mineral – crandallite. A significant amount of clay minerals, particularly those belonging to the smectite group and halloysite, results in high value of the specific surface area (up to 100 m2/g) of the studied crust. Such favorable property of the crust makes it a promising sorptive raw material that can be applied, even in an unprocessed form, for waterproofing. It must be emphasized that the sorption properties of basalt weathering crusts were noticed some centuries ago in the western part of Lower Silesia, where medicine called terra sigillata was produced from them. Moreover, the crust from Rutki was also used in the XIXth century, in a ceramic manufacture located in nearby Tułowice, where the so-called “Silesian black porcelain” was produced.