We got used to the idea that the rocks almost eternal, and if you change your appearance, it is only destroyed under some external influence. In fact, the process of formation of minerals, including rock-forming, is constant, i.e., it can be argued that the usual immutable stones can... to grow. Stone called any hard rock, nonseparated in the water. In a broad sense, the stones can be attributed to minerals are crystalline natural substances of inorganic origin.
Depending on sources of energy the processes of formation of minerals can be divided into three groups. A large part of the minerals formed by metamorphic processes deep within the Earth under high temperatures and pressure. So there are deep rocks.
Magmatic processes associated with the solidification of the magma, composed mainly of silicates, but at the same time containing all the known elements. Crystallization of the magma leads to the formation of a large number of different minerals, and since this process is accompanied by gradual decrease in temperature within the basic rocks occur new. The result is a so-called pegmatite veins natural museums of Mineralogy. Through the cracks of the earth's crust inside rocks already secretaryoffice penetrate the volatile compounds under the action of which existing minerals change, forming new. Exactly what is inside granite formed the greisen – special rocks, composed of quartz, mica, Topaz and rare items.
Exogenous processes of mineral formation are related to external factors: atmospheric conditions, temperature variations and the influence of groundwater micro-organisms, plants and finally man. The resulting minerals are called supergene, i.e. re-formed. Thus appear and "grow" saltlike minerals, limestone, chalk, etc.
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