Mica is a naturally occurring, highly platy phyllosilicate of aluminium and potassium that occurs in book-like form that can be easily split into extremely thin, often transparent sheets that are both tough and flexible. Mica is fairly widespread and occurs in igneous, metamorphic and sedimentary rocks. Large mica crystals are typically mined from granitic pegmatites.
Only very few crystals are industrially mined. Muscovite white mica is the most common commercial form, accounting for 90 % of global consumption, followed by phlogopite, a bronze-colored variety. Mica is unique among platy minerals due to the broad range of particle sizes naturally available from microns up to several centimeters and even meters!
Imerys mines and processes both muscovite and phlogopite mica to serve the plastics, paints, ceramics, sound-damping and cosmetics markets.
Mica is a naturally occurring phyllosilicate of aluminium and potassium with the chemical formula composed of:
Muscovite KAl2(AlSi3O10)(F,OH)2 and
Phlogopite KMg2(AlSi3O10)(F,OH)2
Physical properties
- Gas and liquid barrier
- Chemical resistance
- Thermal conductivity
- Heat stability
- Passive fire retardancy
- Low coefficient of friction
- Hydrophilic
- Flexible
- Vibration damping (acoustics)
High-performance minerals for a wide range of end uses
Multi Mineral Processing focuses its attention on the supply of platy micas for the polymers, coatings and construction and cosmetics industry.
In plastics, mica’s temperature-independent, flexible properties make it an ideal ingredient in the production of complex injection-moulded parts where it improves flexural modulus and heat deflection temperature and contributes to reducing shrinkage and warpage. Mica can also be used in polyamides for the partial replacement of glass fiber.
Used in rubber compounds, Multi Mineral Processing mica is an effective flame retardant extender and ideal all-around multi-functional additive.
In paints and coatings, the particle shape and chemical composition of Multi Mineral Processing micas provide good chemical and corrosion resistance. Mica is also used as an anti-cracking agent and improves weather and UV resistance of external coatings. Thanks to its lamellar shape, mica gives as well anti-staining properties in decorative coatings.
In structural vibration damping applications, mica improves the loss factor of damping materials when applied on steel sheets used in car bodies and domestic appliances such as dishwashers.
In fiber cement construction panels mica improves fire resistance by reducing panel shrinkage and is ideal for use in wet room fiberboard. Imerys mica is also used as a fire-resistant material in cementitious spray mortars where it provides heat shielding to steel beams, extending building exit time during fires.
In cosmetics, Multi Mineral Processings micas are excellent 100% natural ingredients for make-up compact powders where they provide excellent cohesiveness and transparency.
The global mica market is projected to witness high growth in the coming years owing to surging mica applications in the automotive and electronics industry. With decades of combined mica expertise at our fingertips, Multi Mineral Processing is poised to meet growing demand.