Laterite is a soil type that is rich in iron and aluminum and is commonly found in hot and wet tropical areas. It is nearly always of a rusty-red color due to its high iron oxide content. Laterite is a residual material that is left behind after common silicate rocks undergo a type of chemical weathering known as laterization or lateritization. Laterite is composed of iron, aluminum, titanium, and manganese oxides, with iron-rich varieties consisting of hematite and goethite. Laterite is not uniquely identified with any particular parent rock, geologic age, single method of formation, climate per se, or geographic location. Laterite is used as a construction material, especially in Asia, and can be cut into regular-sized blocks when moist. Lateritic soil almost lacks fertility and is generally not suitable for agriculture.