Hydrous aluminium Class of hydroxyl-bearing silicate minerals with a sheet-like structure. They result from aqueous alteration are dominantly serpentine and smectite in meteorites; found in the matrixes of carbonaceous chondrites. Phyllosilicates consist of repeating sequences of sheets of linked tetrahedra (T) and sheets of linked octahedra (O). The T sheet consists of Click on Term to Read More, with variable amounts of Fe, Mg, Ca, Na, K, and other cations. The structure of clay minerals is similar to that of micas, consisting of alternating octrahetral and tetrahedral sheets. They are common weathering products of An alumino-silicate mineral containing a solid solution of calcium, sodium and potassium. Over half the Earth’s crust is composed of feldspars and due to their abundance, feldspars are used in the classification of igneous rocks. A more complete explanation can be found on the feldspar group page. Click on Term to Read More and low temperature hydrothermal alteration products.
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