Take pearlescent pigments as an example, pearlescent pigments are a class of pigments with pearl luster, which are deposited on the substrate (generally natural mica, synthetic mica, glass sheet and other sheet-like materials) above a layer or alternately deposited multiple layers of metal oxides or non-metallic oxides and formed a flat sandwich body with a structure similar to sandwich. Due to the difference in refractive index between the substrate and the oxide deposited on its surface and each oxide, when the light shines on the surface of the pearlescent pigment, the incident light will be refracted and reflected at the interface of each layer of the pearlescent pigment, and the color of the pearlescent pigment that people see is the result of the superposition of light after multiple refractions and reflections of the light, that is, the interference phenomenon of light.

Natural mica powder and synthetic mica powder have differences in production methods, heat resistance and color transparency. As the name suggests, natural mica powder is made from natural mica ore after processing, retaining the original characteristics and composition of the ore. Its main components are SiO2 (about 49%) and Al2O3 (about 30%), while also containing K2O+Na2O (9%-11%) and so on. The synthetic mica powder (such as fluoroglogopicite powder), is the use of a variety of raw materials through high temperature reaction and other chemical methods synthetic, its composition and characteristics can be adjusted and optimized according to the need, the chemical formula is KMg3(AlSi3O10)F2, belongs to the monoclinic crystal system, is a typical layered silicate, relatively single and pure composition. The heat resistance of natural mica powder is generally 500-600℃, and some types, such as phlogopite, can reach 800℃. The heat resistance of synthetic mica powder is more excellent, and it can withstand high temperatures above 1200℃, and the melting point or crystallization temperature is about 1375±5. The transparency of natural mica powder is relatively low, and the color is diverse, including black, yellow, white, gray, green, brown and other colors, and may vary due to different ore types and processing methods. The color of synthetic mica powder is relatively single, usually colorless transparent or white, high whiteness, good optical performance, and high transmittance from ultraviolet to infrared band.

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.

5. Paints and Coatings Flogopita is also used as a pigment in paints and coatings, providing not only color but also adding durability and resistance to wear and tear.

Mica is a very common rock-forming mineral, widely distributed in crystalline rocks. Its general chemical formula can be expressed as: