granite and marble differences

 Granite is igneous intrusion by the underground magma cooled and crystallized, and granitic rocks like. Crystal structure and with visible texture. It consists of feldspar (usually potash feldspar and oligoclase) and green concrete blades  quartz, mixed with a small amount of mica (biotite or muscovite) and trace minerals, such as: zircon, apatite, magnetite, ilmenite and sphene and so on. Granite main ingredient is silica, the  concrete core bits content of about 65% - 85%. The chemical properties of granite is weakly acidic.Under normal circumstances, whitish or gray granite, because mixed with dark crystal, with the appearance of spots, feldspar join makes it red or flesh-colored. Granite is formed by the crystallization of magma cooled slowly, deep below the surface, when the cooling rate is unusually slow when it forms a very rough texture of granite, known as pegmatite. Granite and other crystalline rocks form the basis of continental plates, it is also exposed to the surface of the earth is the most common intrusive rocks.Although granite is considered by melting the material or the formation of igneous magma, but there is plenty of evidence that some form of granite rock is locally deformed or previous product, they do not go through the process of a liquid or melted to rearrange and recrystallization.The proportion of granite between 2.63 to 2.75, the compressive strength of 1,050 ~ 14,000 kg / sq cm (15,000 to 20,000 pounds / square inch). Because the  sanding paper intensity ratio of sandstone granite, limestone and marble, it is more difficult to exploit. Since the formation of the special conditions of granite and structural characteristics of the firm