BauxiteBauxite is not a mineral, (is is in S.O.) but rather a group of aluminum oxides. The term is generally used to describe the economically important mixture of these minerals, which form a mass of the individually classified members of Gibbsite, Boehmite, and Diaspore. Bauxite does not make aesthetic or interesting specimens as far as collectors are concerned, but it holds importance as being the primary ore of the metal aluminum. Bauxite is named after the French village of Les Baux, where it was first recognized as an aluminum ore.
http://www.minerals.net/mineral/bauxite.aspx Goethite/LimoniteGoethite is a very common mineral, and is a frequent matrix material for other more aesthetic minerals. It is usually an ugly dark mineral, though specimens from a handful of locations (especially Colorado) are remarkable for their delicate and beautiful crystal growths or oddly formed botryoidal and stalactitic velvety growths. Goethite is also frequent as black crystal sprays that form within geodes on drusy Quartz. It commonly forms a pseudomorph after other minerals, especially Marcasite, Pyrite, Siderite, and Gypsum. Limonite is basically the same thing.
http://www.minerals.net/mineral/goethite.aspx http://www.minerals.net/mineral/limonite.aspx |
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