Nickel formed with silicate minerals rich in elements Mg (ex; olivine). Olivine is a mineral which is unstable during weathering took place. Saprolite is the first weathering product, leaving at least 20% of the original fabric of the rock (parent rock). Boundary between bedrock, saprolite and wathering front unclear and even changes gradasional. Laterite nickel deposits are characterized by the existence of speroidal weathering along joints and fractures (boulder saprolite). During weathering progresses, Mg silicates are soluble and dissolve with groundwater. This causes the fabric of parent rock is totally change. As a result, Fe-Oxide dominated by forming horizontal layers above the saprolite, which we now know as limonite. It is true that nickel is associated with Fe-Oxide mainly of type Goethite. The average nickel amounted to 1.2%.
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