Granite is one of igneous rocks, which is widely distributed in the crust, and is a crystalline rock formed by magma cooling and condensation in the deep crust. The main components are quartz, feldspar and mica. Generally, it is yellow with pink, and it is also gray and white. It is a good building material with hard texture and beautiful color. It is commonly known as granite.
Granite is a deep-formed acid igneous rock formed by magma condensation in the deep underground. Some of the granites are gneiss or migmatized rocks formed by metamorphism of magma and sedimentary rocks. The main composition minerals of granite are feldspar, quartz, biotite, etc., and the quartz content is 10% - 50%. Feldspar content is about 2/3 of the total, which is divided into orthoclase, plagioclase (alkali lime) and microcline (potash). Different varieties of mineral composition are different, and pyroxene and amphibole may also be present.
Density: 2790-3070 kg/m3
Compressive strength: 1000-3000 kg/cm2
Modulus of elasticity: 1.3-1.5x106 kg/cm3
Water absorption: 0.13%
Shore hardness: > HS 70
Specific gravity: 2.6-2.75
Granite has its unique physical characteristics and beautiful patterns, which makes him a good material for architecture. It is known as "the king of rock". Others use one view, two quantity, three listening and four tests to evaluate the quality. Granite can be used from roof to floor in buildings, and sidewalk kerbs can be crushed to fill dams with cement or rock. Many places or objects that need to be weather resistant or need to survive are made of granite. Signs like Taipei's "Zhongzheng Memorial Hall" and the monument to the people's Heroes in front of Tian'anmen in Beijing are made of granite. Granite has been a characteristic of the past millennium, as evidenced by the famous Egyptian pyramid.
Commercial granite includes the granite and gneiss mentioned above, gneiss, granite and rocks with the composition of syenite and granodiorite as the scholars call them. Gneiss rocks include mineral composition, granite like and granular crystal organizer. Commercial granite also includes other similar structures and feldspar crystals with a small amount of bycomponent minerals, mainly used for decoration, as the rock scholars call Calc plagioclase. Gneiss is a coarse crystalline rock, mainly composed of silicate minerals, which are inlaid and granular crystal. Different types of minerals are arranged in regular or irregular ways. Granite classification according to the American Society for testing materials.