Search results
Results from the WOW.Com Content Network
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al 2 Si 4 O 10 (OH) 2. It occurs in two forms ( habits ): crystalline folia and compact masses; distinct crystals are not known.
The Si-O-M linkage between the silicates and the metals are strong, polar-covalent bonds. Silicate anions ([SiO 2+n] 2n−) are invariably colorless, or when crushed to a fine powder, white. The colors of silicate minerals arise from the metal component, commonly iron. In most silicate minerals, silicon is tetrahedral, being surrounded by four ...
The degree of hydration of the cations and their corresponding hydrated radii explain the swelling or the shrinking behaviour of phyllosilicates. Other cations such as Mg 2+ and K + ions exhibit even a more contrasted effect: highly hydrated magnesium ions are "swellers" as in vermiculite (totally expanded interlayer) while poorly hydrated ...
Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al 2 Si 2 O 5 4), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces. Clay minerals form in the presence of water [1] and have been important to life, and many theories of abiogenesis ...
When treated with calcium oxides and water, silicate minerals form Portland cement. Equilibria involving hydrolysis of silicate minerals are difficult to study. The chief challenge is the very low solubility of SiO 4 4-and its various protonated forms. Such equilibria are relevant to the processes occurring on geological time scales.
Phyllosilicates are sheet silicate minerals, formed by parallel sheets of silicate tetrahedra with Si 2 O 5 in a 2:5 ratio. Subcategories. This category has the ...
Illite is a secondary mineral precipitate, and an example of a phyllosilicate, or layered alumino-silicate. Its structure is a 2:1 sandwich of silica tetrahedron (T) – alumina octahedron (O) – silica tetrahedron (T) layers. [ 5 ]
In a fine powder form, it can also be used as a flocculant in ponds. Tossed on the surface as it drops into the water, making the water "clouded", it attracts minute particles in the water and then settles to the bottom, cleaning the water. Koi and goldfish (carp) then actually feed on the "clump" which can aid in the digestion of the fish.