(White marble railing and its composition) What are their names?

In daily life, we can often see marble with elegant tone, clear texture and beautiful pattern. People often use marble to decorate walls, make desktops and various stationery and handicrafts. The railings around the base of the main hall of the Forbidden City in Beijing are made of pure white marble. This pure white marble is called white marble. White marble: It is a kind of crystal-clear white marble with pure white color and crystal-clear crystals, giving people a spotless and solemn aesthetic feeling. The output of white marble accounts for about 30% of the total marble output, and it is mostly used for sculpture portraits, Buddha statues, animals and plants, etc. According to historical records, the exploitation of marble can be traced back to at least before Nanzhao in the Tang Dynasty, and the three pagodas of Chongsheng Temple in Dali in the Tang Dynasty, which were built more than 1000 years ago, have already adopted exquisite marble carving products, with high technical level. Yunnan marble has been widely used in royal tombs in history, such as the Forbidden City in Beijing and the Ming Tombs. Before 1950s, the exploitation and processing of marble remained in the way of manual production. Until 1953, a marble factory was built in Dali, which gradually realized mechanized production, increased product types and improved technology level. In addition to domestic demand, its products are also exported to Southeast Asia and Arab markets. Many people may have seen limestone, the raw material for burning lime, and marble is made of this ordinary gray stone. The "hero" who turns limestone into marble is the fiery magma underground. When magma rushes into a large limestone formation, calcium carbonate particles that make up limestone become crystalline calcite under the extrusion and baking of magma, and unremarkable limestone becomes smooth and beautiful marble with clear patterns. Marble has various colors and textures. White marble is white marble, which is crystal white and contains sparkling crystals. It is a very valuable building material. White marble is mainly composed of CaCO3, MgCO3 and SiO2, and also contains a small amount of Al2O3, Fe2O3 and other components. Reference parameters of materials include whiteness, gloss, compressive strength, bending strength, Shore hardness, water absorption and density. Generally speaking, it is a sedimentary metamorphic deposit formed under the influence of magmatic hydrothermal process and different degrees of hydrothermal metamorphism and dynamic metamorphism. White marble is pure white marble and a form of limestone. Since ancient China, this kind of stone has been used to make stone steps and guardrails of palaces. The so-called "jade bamboo fence" is gorgeous as jade, so it is called white marble. The huabiao in front of Tiananmen Square, Jinshui Bridge, the base of the palace, the stone steps and the guardrails in the palace are all made of white marble.