The synthetic fluorine mica, fluorophlogopite KMg₃(AlSi₃O₁₀)F₂, contains no (OH)^- of the natural phlogopite KMg₃(AlSi₃O₁₀)(OH)₂. The (OH)^- is fully substituted with F^- . Large fluorine mica crystals of high quality are grown by a Bridgman-Stockbarger method using platinum crucibles with seeds. The fluorine mica has the following unique characteristics : highly chemical stability, excellent transmittance, outgasing-free at high temperature in vacuum, excellent electrical insulation, high heat endurance (up to 1100 °C), non-radioactive background, highly flexible and cleavable, which are much superior to that of natural mica.

The synthetic mica sheets are suitable for a variety of uses such as substrates of thin film, windows and monochromater for x-ray, neutron diffraction, microwave and optics, spacers of electrical vacuum devices, supporters at high temperature and water-gauges of high pressure boilers, and etc., which are important in modern industry and most advanced branches of science.

Heat endurance (°C) 1100

Melting temperature (°C) 1378

Density(g/cm³) 2.8

Dielectric strength (KV/mm) ~180

Tensile strength (Kg/cm²) ~1500

Optical indexes : Np=1.5239

Nm=1.5450

Ng=1.5470

Moisture absorption (%) none