Characteristics of sandstone, slate and quartz
Limestone is a kind of rock formed by sedimentary source, which is mainly composed of calcium carbonate, calcium magnesium carbonate or calcium carbonate and magnesium carbonate. Microcrystalline limestone recrystallization limestone, strong and polished lime as Huadu limestone or marble publicity and sales, especially in the United states. According to the different density range, the formation of limestone is divided into three subclasses:Low-density limestone - density range 110~135 lbs / cubic feet (1760~2160 kg / m3).Medium density limestone - density range 135~160 lbs / cubic feet (2160~2560 kg / m3).High density limestone density greater than 160 psi / cubic feet (2560 kg / m3).
Also known as sand rock is sandstone, due to crustal movement of the earth, sand and cement (siliceous material, calcium carbonate, clay, ferric oxide, calcium sulfate) a sedimentary rock formed by long-term pressure compression bonding.
Slate is also a sedimentary rock. The shale that formed the slate first deposited on the mud bed, and later, the movement of the earth caused the shale beds to stack up. The main composition of the slate is silica. Acid resistance. According to the composition of the slate can be divided into three types of slate:(1): the composition of carbonate slate silica content less than 40%, three, two aluminum oxide content is less than 10%, calcium oxide content is less than 15%, Magnesium Oxide was less than 10%, ferric oxide content is 3% - 7%.(2) clay Slate: the main component of sericite, chlorite, illite, kaolin clay minerals, which accounted for more than 80% of the stone mineral composition, silica content of more than 50%, three and two aluminum oxide content is higher than 12%, calcium oxide content is less than 10%, less than 5%, the Magnesium Oxide content was higher than that of ferric oxide carbonate type of slate.(3) carbonaceous, siliceous Slate: between mineral composition between clay slate and carbonate slate, due to strong silicification degree, high silica content, stone rather hard, darker.Performance of slate structure for sheet or block, fine particles, particle size was between 0.9 and 0.001mm is usually hidden crystal structure, more dense, and most are aligned, rock cleavage is development of uniform thickness, moderate hardness, water absorption rate. Its life expectancy is about 100 years.The slate color to monochrome. Such as: gray, yellow, green, gray, green, blue, black, brown, red, purple, etc.. Because a single color pure, in the decoration, gives people a sense of elegant. Slate generally no longer polished, showing the natural form, the formation of the natural beauty.Therefore, the sand and the stone flower color is better than that of marble and granite, the decoration is also used in some rich cultural connotation of the place.
The limestone has many distinctive natural features, such as lines or spots, calcite or fossil shells structure, holes, elongated organization, open texture, honeycomb structure and iron plaque, similar travertine structure and crystallization of the difference. The combination of one or more of these features will affect the quality of the limestone.
