Saprolite (from Greek σαπρος =putrid, + lite) is the name for a chemically weathered rock. It is mostly soft or friable and commonly retains the structure of the parent rock since it is not transported, but autochthonously formed in place.

Besides resistant relic minerals of the parent rock, saprolites contain predominantly quartz and a high percentage of kaolinite with other clay minerals which are formed by chemical decomposition of primary minerals, mainly feldspars. More intense weathering conditions, exceeding the saprolite stage, give rise to a continuous transition to laterite soils.

Pedology | Sedimentology