Granite is represented to the person a true sample of durability, stability. These properties are even associated with eternity, the custom was not without reason approved to make the monuments and tombstones designed to immortalize someone's memory of granite.
In comparison with mankind, granite can really be considered eternal. The age even of the youngest granites contains 2 million years while the age of a type of Homo Sapiens is measured only by dozens of the millennia. The age of the most ancient granites is estimated in billions of years.
Geologists call granite "hallmark" of the planet Earth. Many other rocks meet also on other planets and their satellites having a firm surface, and here granite is not found yet anywhere, except Earth. Meanwhile, all planets of the Solar system were formed of one gas-and-dust cloud. It does a problem of origin of granite especially mysterious.
Background
Geologists of the 18th century connected origin of granite with the ancient ocean. They considered that they from sea water on a bottom settled crystals of which granite was formed. The scientists adhering to such views are called neptunist. At the beginning of the 19th century there was other theory which adherents were called plutonist. They considered what facets volcanic magma generated. These scientists imagined granite formation process as follows: the hot water solutions going from terrestrial depths dissolve some chemical elements which are a part of rocks. Their place is taken by other elements brought by water solutions and granite is formed. Such representation was very far from the truth too. But it is worth to remember that at that time at the disposal of scientists there was few information about structure of granite breeds and the physical and chemical processes happening in earth crust were not quite clear. And yet the direction was right: formation of granite is really connected with magma and volcanic activity.
Modern idea of granite emergence
Process of formation of granite was explained by the American geologist N. Bowen. It connected origin of this rock with crystallization of basalt magma. It explains from where granite could undertake on Earth if it is not on other planets and satellites of the Solar system, basalt breeds are there. Crystallization of mineralll in basalt magma goes in a certain sequence which was called "Bowen's number". There is a gradual enrichment of fusion with various fusible chemical elements – sodium, potassium, silicon. Granite becomes result of this process also. Today it is possible to take magmatic origin of granite for granted. Even modern eruptions of volcanoes quite often take out on a surface the magma close on structure to granite.