—limonitic /luy'meuh nit"ik/, adj./luy"meuh nuyt'/, n. Mineral.an amorphous hydrated ferric oxide, varying in color from dark brown to yellow, used as an ore of iron.[1815-25; < Gk leimón meadow + -ITE1]
* * *One of the major iron minerals, a hydrous ferric oxide of variable composition.Often brown and earthy, it is formed by alteration of other iron minerals, such as the hydration of hematite or the oxidation and hydration of siderite or pyrite.Courtesy of the Field Museum of Natural History, Chicago; photograph, John H. Gerard/EB Inc.
* * *▪ mineralone of the major iron minerals, hydrated ferric oxide (FeO(OH)·nH2O). It was originally considered one of a series of such oxides; later it was thought to be the amorphous equivalent of goethite and lepidocrocite, but X-ray studies have shown that most so-called limonite is actually goethite.The name limonite properly should be restricted to impure hydrated iron oxide (with variable water content) that is colloidal, or amorphous, in character. Often brown and earthy, it is formed by alteration of other iron minerals, such as the hydration of hematite or the oxidation and hydration of siderite or pyrite. It probably bears the same relationship to iron oxides that wad and gummite do to manganese and uranium oxides. Compare goethite.
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