A red residual soil formed because of the leaching of silica and also by enrichment with aluminum and metal oxides, especially in humid climates.
A red tough or gravel-like earth or subsoil created into the tropics which has been leached of soluble nutrients making insoluble metal and aluminium oxides and hydroxides; regularly make bricks and roads.
An argillaceous sandstone, of a red color, and much seamed; -- present in Asia.
A rock of distinct character, present in India many elements of southwestern Asia.
a red soil made by rock decay; contains insoluble deposits of ferric and aluminum oxides