- Dec 04, 2017 -
Granite texture hard and dense, high strength, weathering, corrosion resistance, abrasion resistance, low water absorption, beautiful color but also save more than a century, is a good building materials, but it is not heat-resistant. Granite stone by color, pattern, luster, structure and material and other factors, points at different levels. The Bureau of Mines, Taiwan's Ministry of Economic Affairs, divides the granite into six categories: black, brown, green, off-white, light red and dark red. Although granite is a good material for construction, some parts of the granite spill radon, a natural radioactive gas. Radon can cause lung cancer. In Hong Kong, 13% of lung cancer patients died of excess radon.
Coarse or medium-grained intrusive rock, rich in quartz and feldspar, is the commonest pluton in the crust and is cooled by the magma deep in the crust. As a result of the paving stones and building stones, mining granite was once an important industry and you must need to use granite cutting machine. Granites can be dikes or bedrock output, more representative of the scale of irregular rock mass changes. The main component is feldspar, plagioclase and alkaline feldspar are generally very rich, the relative abundance of both became the basis for the classification of granite. In most granites, the ratio of the two types of feldspar is less than 1/2.Belonging to this category are most of the granites in the eastern, central, and southwestern United States, southwestern England, the Baltic Shield Region, western and central France, Spain and many other regions. Plagioclase greatly exceeds the basic feldspar granite class, common in some parts of the western United States. Granites with much higher alkaline feldspar content than plagioclase are found in many sites in New England, the United Kingdom and Oslo, Norway, but are all smaller ones and are widespread in northern Nigeria. Rocks with less than 20% quartz are not called granites. Dark minerals (mafic minerals) have a maximum content of about 20% by volume.The lesser major minerals in granite are muscovite, biotite, amphibole, pyroxene or rare fayalite. Biotite can be produced in any type of granite and is usually found, albeit at times, in small amounts. Sodium-containing amphiboles and pyroxenes (salsamite, sodiflorat, and aegite) are characteristic of alkaline granites. If neither of the two types of feldspar significantly exceed the other, amphiboles and pyroxenes are unlikely to be the major minerals; the dark minerals are usually biotite or muscovite, or both.