Mica has a wide range of uses, in ancient China, it is often used to do traditional Chinese medicine, the ancients even think that taking mica: a year to remove all diseases (heavy metal poisoning), three years of long service, husband into a boy (body scrap), Zhongshan uncle Qing suit, over time can become a cloud (soul ascension). However, in the era without glass, the transparency of mica makes it a better decorative material, for example, we are familiar with the mica screen candle shadow deep, the river gradually falling Xiaoxing sink. Mica screen is low, tassel tent is small and mica calf car.

X represents large interlayer cations, such as K+, Na+, Ca2+, Ba2+, Rb+, Cs+, etc. Y represents octahedral cations, such as Al3+, Fe2+, Mg2+, Cr3+, Ti4+, Fe3+, etc. Z is mainly Si4+ and Al3+; The ideal ratio of the additional anion (OH)- to (O)2- is 2:10, and (OH)- can be replaced by F- and Cl-. Most mica contain 4% to 5% water. Therefore, although they may be called mica, the chemical composition of different mica may be very different, for the purpose of research, we collectively refer to the minerals with this type of characteristics as mica group minerals.  

Layer upon layer of mica

The common characteristics of mica group minerals are: layered silicate minerals, monoclinic crystal system, a few trigonal crystal system, the crystals are pseudo-hexagonal columnar, plate and sheet; The aggregate is scaly and foliaceous. It has a set of extremely complete cleavage, along which it is easy to peel into sheets. Therefore, the shape of mica is usually regarded as sheet.