mica

CONT: (Les micas forment une famille). [...] Toutes les espèces de la famille des micas sont monocliniques. Le mica existe dans une foule de roches cristallines et constitue l'un des trois éléments fondamentaux du granite.

CONT: Biotite is the ferromagnesian black mica, and muscovite is the potassic white mica. Sometimes mica is used as a lost-circulation material in drilling.
OBS: Synthetic mica is available. It has electrical and mechanical properties superior to those of natural mica ... Use: Electrical equipment, vacuum tubes, incandescent lamps, dusting agent, lubricant, windows in high-temperature equipment, filler in exterior paints, cosmetics, glass and ceramic flux, roofing, rubber, mold-release agent, specialty paper for insulation and filtration, wallpaper and wallboard joint cement, oil-well drilling muds.