Slate is a metamorphic stone formed as a result of mountain building processes. The properties or character of a slate depends on the geological setting during its origin. The chapter describes the depositional environments which comprise mainly the passive continental margins but also back-arc basins or sedimentation in delta facies, governing the sedimentary pattern and colours as well as the mineralogical composition of a slate. It introduces the tectonic settings and metamorphic conditions during the orogeny, leading to different types of slate in respect to stone type such as slate s.s., schist or gneiss. These stones are all more or less fissile and used for roofing and for other architectonical purposes.The metamorphic processes, different tectonic settings and positions in an orogenic belt as well as the related fold styles are explained in this chapter. The main result of the deformation during folding in respect to slate is the cleavage plane, governing its fissility. The cleavage plane is strongly related to folds which occur in various forms that can be classified depending on the tectonic position in the orogenic belt. The chapter describes the structural elements such as folds, faults and joints and their influence to the mining process as well as the properties of a slate.