Laterite
Laterite is a red-colored clay-like kind of soil found in the tropic areas. It is an infertile soil, but bricks made out of dried laterite make a good building material. Most of the temples of the Khmer empire in South-East Asia are built with this material and survived for 1000 years already.The name Laterite derives from the Latin word later meaning brick, referring to the red brick-like color. Laterite needs the high temperatures of the tropics and the abundant rainfalls to form. The water washes out the bases and the silicic acid, and enriches it with aluminum silicates, aluminum hydrosilicates, iron oxides and iron hydroxides. Especially the iron leads to the typical red color.