Lateritic nickel ore deposits Wikipedia
Limonite type laterites (or oxide type) are highly enriched in iron due to very strong leaching of magnesium and silica. They consist largely of goethite and contain 12% nickel incorporated in goethite. Absence of the limonite zone in the ore deposits is due to erosion. Silicate type (or saprolite type) nickel ore formed beneath the limonite