Limonite << LY muh nyt >> is a yellowish or brownish mineral deposit. It is a kind of iron ore composed of varying amounts of the minerals goethite, hematite, and lepidocrocite.
Limonite results from the breakdown and weathering of other minerals that contain iron. It may occur as a surface film on rocks, as ordinary rust, or as a slimy deposit in lakes and marshes. Limonite also may appear as the coloring material in yellow clays and soils. It is the source of ocher, a yellow powder used in paints and pigments.
Limonite is found in large amounts in Cuba, in eastern France, and in the Labrador Trough region of eastern Canada. Limonite originally referred to a type of iron deposit now called bog iron ore.
See also Iron and steel (Kinds of iron ore).