Granite is one of the most common rocks on earth.

Natural granite consists of minerals such as quartz, plagioclase, potassium feldspar, biotite, Muscovite. Most of the granite - about 60% - is feldspar; about 30% - quartz and 5-10% accounts for biotite.
If we consider the features of the mineral composition of various natural granites, we can distinguish two varieties: plagiogranite and Alaskan. Plagiogranite has a light gray color and has a high content of plagioclase. Alaskite has a pinkish or pink-red color; it is characterized by a high content of potassium-sodium feldspar.
If we consider the structural features of granite, porphyry granite is isolated separately, which has characteristic inclusions ("grain") of different sizes. In turn, porphyry granite, whose grains are overgrown with light gray plagioclase, is called rapakivi granite (translated from Finnish, - "rotten stone"). This is due to the fact that this structure of granite reduces its strength, and therefore rapid destruction of the rock.
However, granite is one of the hardest, densest and most durable natural stones. Its average density-2600 kg / m3, and compressive strength - up to 300 MPa. Also granite has low water absorption and high resistance to low temperatures and pollution, which makes it an ideal material for use in construction.