Shale is a widespread rock with a special, layered structure consisting of parallel arranged, pressed together various minerals. The origin of the rock is associated with active centuries-old processes in the thickness of the earth's crust or at the bottom of the seas (the impact of temperature, pressure, water and gas solutions). Most of the oil shale mined nowadays is more than 300 million years old!

Therefore, all types of shale mainly have a heterogeneous color and different hardness. Thus, on the Mohs scale, the hardness of shale can range from 2 to 6 points. The color of slate can be grayish, whitish, brownish, black, greenish and reddish. The rock also differs in its structure; there are siliceous shale, clay shale, crystalline shale, oil shale, etc. Accordingly, the moisture resistance of the rock, depending on the porosity, can also vary from 0.01% to 3%.
Currently, slate has a very wide application. In construction it is used as a finishing or roofing material; in landscape design – as an element of decor, borders, steps, artificial rocks, etc.
Used oil shale to get oil and tar, used as fuel for thermal power plants, as raw material for the manufacture of glue, chemicals, drugs, etc.
Fuchsite slate (fuchsite), with a beautiful green tint, refers to semi-precious ornamental stones. From it cut out various figures, balls, beads, etc.