Methods of deep purification of natural and isotopically enriched cadmium (Cd, 106Cd, 116Cd), as well as of archaeological lead (archPb), to produce cadmium and lead tungstate crystal scintillators have been developed. The basic stages of development and characteristics of the scintillators are described. The developed methods of initial materials purification and crystal growth can be used for the production of scintillators for large-scale high sensitivity experiments to search for rare events (double beta decay, dark matter, rare alpha and beta decay).