Due to weathering of serpentinite containing a small amount of nickel, the nickel component becomes concentrated and nickel-containing clay including nickel minerals such as garnierite which is secondarily generated from the weathering is distributed.
この少量のニッケルを含む蛇紋岩の風化によりニッケル分が濃縮され二次的に生成した珪ニッケル鉱などのニッケル鉱物を含む含ニッケル粘土が分布している。