The thick (from 5 to 20 m and more) clayey weathering crust in the South Urals is a product of deep physical and chemical processing and disintegration of Paleozoic rocks in the Mesozoic. Clays (60%), medium and heavy loams (30-35%) prevail. The results of statistical processing of tests of 102 monoliths indicate the heterogeneity of properties, especially the strength characteristics of rocks.