The Black Shales of the Early Paleozoic age are the important mineral resource of Sweden. They are specialized in uranium, vanadium, molybdenum and several chalcophile elements. For the long history of development of deposits in adjacent areas many quarries and outcrops were formed, in which, under surface conditions, the process of chemical weathering is actively proceeding, characterized by the formation of secondary minerals inheriting geochemical specialization of the parent rocks.
Black shales accumulate (up to, ppm): U- 216, V - 1410 θ Mo 411, and clarke of concentration is: U 8,3; V 3,2; Mo 12,5. Part of the chemical elements is in the water-soluble form, the coefficient of accumulation in which in comparison with the gross composition of the black shales is: Co 16,1; Ni 15,8; Zn 10,9; U 4,2; Mo 1.
Secondary minerals accumulate (up to, ppm): U - 230, V 510, Mo 165, Zn 410, V 510, Sr 970, Ba - 350.
In the conditions of hypergenesis, a wide range of elements of different hazard classes can migrate into the environment and participate in biological cycles.
Keywords: black shales, geochemistry, geochemistry of nanofractions.