[10] The crystal structure of mica is described as TOT-c, meaning that it is composed of parallel TOT layers weakly bonded to each other by cations (c).

The remaining negative charge of the TOT layer is neutralized by the interlayer cations (typically sodium, potassium, or calcium ions).

[20] Flake mica comes from several sources: the metamorphic rock called schist as a byproduct of processing feldspar and kaolin resources, from placer deposits, and pegmatites.

These sheets are chemically inert, dielectric, elastic, flexible, hydrophilic, insulating, lightweight, platy, reflective, refractive, resilient, and range in opacity from transparent to opaque.

It has superior electrical properties as an insulator and as a dielectric, and can support an electrostatic field while dissipating minimal energy in the form of heat; it can be split very thin (0.025 to 0.125 millimeters or thinner) while maintaining its electrical properties, has a high dielectric breakdown, is thermally stable to 500 °C (932 °F), and is resistant to corona discharge.

Phlogopite mica remains stable at higher temperatures (to 900 °C (1,650 °F)) and is used in applications in which a combination of high-heat stability and electrical properties is required.

[21] The leading use of dry-ground mica in the US is in the joint compound for filling and finishing seams and blemishes in gypsum wallboard (drywall).

The coarsely ground mica flakes help prevent the loss of circulation by sealing porous sections of the drill hole.

The plastics industry used dry-ground mica as an extender and filler, especially in parts for automobiles as lightweight insulation to suppress sound and vibration.

Mica is used in plastic automobiles fascia and fenders as a reinforcing material, providing improved mechanical properties and increased dimensional stability, stiffness, and strength.

The coating is not absorbed by freshly manufactured roofing because mica's platy structure is unaffected by the acid in asphalt or by weather conditions.

Dry-ground phlogopite mica is used in automotive brake linings and clutch plates to reduce noise and vibration (asbestos substitute); as sound-absorbing insulation for coatings and polymer systems; in reinforcing additives for polymers to increase strength and stiffness and to improve stability to heat, chemicals, and ultraviolet (UV) radiation; in heat shields and temperature insulation; in industrial coating additive to decrease the permeability of moisture and hydrocarbons; and in polar polymer formulations to increase the strength of epoxies, nylons, and polyesters.

[21] Wet-ground mica, which retains the brilliance of its cleavage faces, is used primarily in pearlescent paints by the automotive industry.

This acts as a mild abrasive to aid the polishing of the tooth surface and also adds a cosmetically pleasing, glittery shimmer to the paste.

Specific high-temperature mica-insulated wire and cable are rated to work for up to 15 minutes in molten aluminium, glass, and steel.

Major products are bonding materials; flexible, heater, molding, and segment plates; mica paper; and tape.

The molding plate is sheet mica from which V-rings are cut and stamped for use in insulating the copper segments from the steel shaft ends of a commutator.

Some types of built-up mica have bonded splittings reinforced with cloth, glass, linen, muslin, plastic, silk, or special paper.

These products are very flexible and are produced in wide, continuous sheets that are either shipped, rolled, or cut into ribbons or tapes, or trimmed to specified dimensions.

The sheet of mica is placed on top, acting as a separator between the heat source and the incense, to spread the fragrance without burning it.

High-quality block mica is processed to line the gauge glasses of high-pressure steam boilers because of its flexibility, transparency, and resistance to heat and chemical attack.

[31] Thin transparent sheets of mica were used for peepholes in boilers, lanterns, stoves, and kerosene heaters because they were less likely to shatter than glass when exposed to extreme temperature gradients.

Natural mica was and still is used by the Taos and Picuris Pueblos Indians in north-central New Mexico to make pottery.

Tewa Pueblo Pottery is made by coating the clay with mica to provide a dense, glittery micaceous finish over the entire object.

[21] Mica flakes (called abrak in Urdu and written as ابرک) are also used in Pakistan to embellish women's summer clothes, especially dupattas (long light-weight scarves, often colorful and matching the dress).

The gulal and abir (colored powders) used by North Indian Hindus during the festive season of Holi contain fine crystals of mica to create a sparkling effect.

Earlier examples are found among paper decorations, with the height as the Nishi Honganji 36 Poets Collection, codices of illuminated manuscripts in and after ACE 1112.

For metallic glitter, Ukiyo-e prints employed very thick solution either with or without color pigments stencilled on hairpins, sword blades or fish scales on carp streamers (鯉のぼり, Koinobori).

[44][45][46] Ayurveda, the Hindu system of ancient medicine prevalent in India, includes the purification and processing of mica in preparing Abhraka bhasma, which is claimed as a treatment for diseases of the respiratory and digestive tracts.

Substitutes include acrylate polymers, cellulose acetate, fiberglass, fishpaper, nylon, phenolics, polycarbonate, polyester, styrene, vinyl-PVC, and vulcanized fiber.