Polishing powder is usually composed of cerium oxide, aluminum oxide, silicon oxide, iron oxide, zirconium oxide, chromium oxide and other components. Different materials have different hardness and different chemical properties in water, so the application occasions are different. Alumina and chromia have a Mohs hardness of 9, ceria and zirconia have a Mohs hardness of 7, and iron oxide is lower. 

Cerium-based rare earth polishing powder is one of the more important rare earth products. Because of its strong cutting ability, short polishing time, high polishing accuracy, and clean operating environment, it has better use effect than other polishing powders (such as Fe2O3 red powder), and is called "the king of polishing powder". At present, the product is developing rapidly in our country, its application is increasing day by day, its output has soared, and its development prospect is promising. 

Red powder (iron oxide) is a polishing material used earlier in history, but its polishing speed is slow, and the rust-colored contamination cannot be eliminated. With the development of the rare earth industry, in the 1930s, the use of rare earth oxides as polishing powders to polish glass first appeared in Europe. During World War II, a rare earth oxide polishing powder called Barnesite was proposed in 1943 by an employee of WF and Barnes J in Rockford, Illinois. Quick success in polishing precision optics. Because rare earth polishing powder has the advantages of high polishing efficiency, good quality and low pollution, it has stimulated research in the United States and other countries. In this way, the trend of rare earth polishing powder to replace traditional polishing powder has developed rapidly. 

Foreign countries began to produce rare earth polishing powder 60 years ago. In the 1990s, various standardized and serialized products have been formed with more than 30 specifications and grades. 

At present, there are mainly 15 foreign manufacturers of rare earth polishing powder (with an annual production capacity of more than 200 tons). Among them, the French Rhodia company's annual production capacity is more than 2,200 tons. It is the largest manufacturer of rare earth polishing powder in the world. The annual production capacity of polishing powder in the United States is more than 1,500 tons.

The raw materials for producing rare earth polishing powder in Japan are bastnaesite, crude cerium chloride and rare earth chloride, and the processes are different. The production of rare earth polishing powder in Japan is unique in sintering equipment and technology.

In 1968, my country successfully developed rare earth polishing powder in Shanghai Yuelong Chemical Plant. Subsequently, Northwest Optical Instrument Factory and Yunnan Optical Instrument Factory successively used monazite as raw material, and successfully developed different types of rare earth polishing powder.

Beijing Nonferrous Metal Research Institute, Beijing Institute of Technology and other units developed and promoted the 739 rare earth polishing powder in 1976, and successfully developed the 771 rare earth polishing powder in 1977.

At present, there are 14 rare earth polishing powder manufacturers in China (with an annual production capacity of more than 30 tons), and the largest one has an annual production capacity of 2,220 tons. However, compared with foreign countries, there is still a big gap. The main reason is that the product quality of rare earth polishing powder is unstable, it has not been standardized and serialized, and it cannot fully meet the polishing requirements of various industrial fields, so it must catch up.