Аннотация:Ochrous and red-colored soil profiles are formed on sulfide-containing carbonic (shungite) shales in Karelia. Oxidation of sulfides results in leaching of shungite carbon, the loss of exchange bases from the absorbing complex, and an increase in acidity. Soil color is caused by the presence of goethite, hematite, and jarosite. Biotite, vermiculite, and mixed-layer mica-vermiculite with a tendency for ordering occur in the clay fraction.