The mica variety that does not contain iron is colorless in flakes, and the higher the iron content, the darker the color, and the more polychromatic and absorbable it is. According to the different chemical composition and optical characteristics, mica group minerals can be divided into Muscovite subgroup, biotite-phlogopite subgroup and lemica subgroup. The common mica are biotite, phlogopite, Muscovite and so on.

Natural mica powder and synthetic mica powder also have great differences in electrical insulation, mechanical properties, chemical stability, application range and cost. Natural mica powder has good electrical insulation, but the volume resistivity is lower than that of synthetic mica. Synthetic mica powder has better electrical insulation properties, high volume resistivity and stable dielectric constant, and is suitable for high performance electrical insulation materials. The hardness of natural mica powder is relatively low (2-3), and it has good elasticity and peeling property. The hardness of synthetic mica powder is higher (between 3 and 4), and the tensile strength and compressive strength are better than that of natural mica powder. Natural mica powder is stable in acid-base solution, but it is easy to decompose at high temperature. Synthetic mica powder is stable to acid and base at room temperature, but will be slowly corroded by sulfuric acid above 300℃. Better thermal stability, not easy to release gas. Natural mica powder is widely used in electrical appliances, welding rods, rubber, plastics, paper making, paint and other fields. Synthetic mica powder is mainly used in high-end electrical insulation materials, aviation, aerospace, national defense industry and other high-tech fields. Because synthetic mica powder needs to be produced through complex chemical processes, its production cost is usually higher than that of natural mica powder. Therefore, in the market, the price of synthetic mica powder is often higher than that of natural mica powder. However, with the continuous progress of production technology and the gradual emergence of scale effects, the price of synthetic mica powder is expected to gradually decrease.

Mica is a new non-metallic crystal material, a national key new material, with heat insulation, insulation, high temperature resistance characteristics, is an important material in aerospace, rail transit, nuclear power, wind power, aircraft carriers and other high-tech fields, but also electrical equipment, wire and cable, household appliances indispensable insulation material, in the national economy and national defense construction plays an important role.

For example, the safe operation of high-speed rail cannot be separated from the escort of mica products.