Limonite
The limonite is a cluster of Hydroxyde S of microcrystalline Fer. Mineral sedimentary fundamental, it contains Goethite and Lépidocrocite, plus minor quantities of Hématite, hydroxides of Aluminum, Silice colloidal, minerals argillaceous, Phosphate S, Arséniate S and made up organics. Limonite is the component main thing of the Chapeau of iron . With higher temperature with that of surface, limonite can lose water and be transformed into Hématite.
Limonite presents noirâtre, but when it is moulded becomes yellowish. Limonite is formed by surface deterioration several minerals of Fer, in particular Sidérite, Magnétite, Pyrite. In Iron and steel industry, limonite has little value, because of its contents in Phosphate S and Arséniate S.