1. Tin ore imports continue to decline. This year, with the vaccination of COVID-19 vaccine, the tin mine terminal market is booming. With the increase of demand, the consumption of tin inventory is accelerated. In this case, the price of tin continues to rise. 2. In terms of inventory, LME inventory decreased from 265,438+005 tons at the end of last year to 65,438+0385 tons, a decrease of 720 tons over the previous year. The low inventory of LME has caused the market to pay attention to tin metal. It is found that the fundamental contradiction between supply and demand is very strong. In the current environment, it is difficult to solve this problem in a short time, and then the price of tin began to rise rapidly. 3. From the spot quotation of foreign traders, the promotion level of spot quotation is generally high according to different regions. However, such a large amount of water has attracted only about 500 tons of delivery in Klang Port, Malaysia, while several smelters near the delivery warehouse have done nothing. The American and Dutch warehouses, which kept the inventory low, kept the inventory below100t for nearly one month. High overseas premium and low inventory can also reflect the increase in overseas demand. The prices of a large number of commodities generally began to rise, among which the prices of tin and copper hit a new high in the past eight years. Once, the Federal Reserve released a loose signal, and foreign countries began to expect inflation and recovery, and the vaccination rate in foreign countries gradually increased. The strong superposition of fundamentals opens up procyclicality, and the rising trend of tin price is determined. Information: 1. The English name of tin is tin, and the symbol of element is Sn. It is a metallic element and an inorganic substance. White tin is a common form and a low melting point metal with silvery white luster. It is divalent or tetravalent in the compound and will not be oxidized by air at room temperature. In nature, it mainly exists in the form of dioxide (cassiterite) and various sulfides (such as cassiterite). Tin is one of the famous "hardware"-gold, silver, copper, iron and tin. In ancient times, people discovered and used tin. Tin cans, candlesticks and other tin products can often be found in some ancient tombs in China. According to research, in the Zhou Dynasty in China, the use of tin ware was very common. Tin daily necessities were also found in ancient tombs in Egypt. Tin is malleable at room temperature. Especially at 100℃, it has excellent ductility and can be developed into extremely thin tin foil. People usually wrap cigarettes and sweets with tin foil to protect them from moisture (in recent years, China has gradually replaced tin foil with aluminum foil. Aluminum foil and tin foil are easy to distinguish-tin foil is much brighter than aluminum foil). However, tin has poor ductility. It breaks when you pull it, and you can't pull a single thread. In fact, tin is malleable only at room temperature. If the temperature drops below-13.2℃, it will gradually become loose powder like coal ash. Especially at -33℃ or in alcohol solution containing red salt (sncl 4·2nh 4·cl), the speed of this change is greatly accelerated. A good tin can will automatically turn into a pile of powder. This "disease" of tin can also be transmitted to other "healthy" tin utensils, which is the so-called "tin plague" The reason of tin plague is that the lattice of tin has changed: at room temperature, tin has a tetragonal crystal structure, which is called white tin. When you bend a tin bar, you can often hear a crack. This is because square white tin crystals rub against each other and make a sound when bending. Below-13.2℃, white tin becomes amorphous gray tin. As a result, the tin block turned into a mass of powder. Because tin is afraid of cold, we should pay special attention not to freeze tin products in winter. Many rail cars are generally soldered with tin and cannot be cold. 19 12, a foreign Antarctic expedition went to explore the Antarctic. All used fuel tanks are welded. In the Antarctic ice and snow, solder turned into gray powdery tin, and gasoline leaked out. Tin is afraid of both cold and heat. Above 16 1℃, white tin is transformed into orthorhombic tin with orthorhombic crystal structure. Oblique tin is brittle, it will break when knocked, and its ductility is poor. It is called "brittle tin". White tin, gray tin and brittle tin are three allotropes of tin. Tin is inert and does not react with air or water. React with concentrated hydrochloric acid to generate stannous chloride; Does not react with dilute sulfuric acid, but reacts with concentrated sulfuric acid to generate tin sulfate (_); Production of β-stannic acid with concentrated nitric acid.