Vermiculite is the geological name given to a group of hydrated laminar minerals which are aluminium-iron-magnesium silicates, resembling mica in appearance. Rock and other impurities are removed from the crude ore which is then crushed and sorted into sizes. Vermiculite is a safe inert material, light in colour. When heated it expands (exfoliates) up to 30 times its original volume. The exfoliation process converts the dense flakes of ore into lightweight porous granules containing innumerable minute air layers. Exfoliated (expanded) vermiculite is light and clean to handle, has a high insulation value, acoustic-insulating properties and will absorb and hold a wide range of liquids.

These granules are non-combustible, and are insoluble in water and all organic solvents. Expanded vermiculite is easily poured, is light, clean, highly absorbent and provides baffle against impact shock when used for packaging.

Exfoliated vermiculite is used in the friction brake linings market, high temperature insulation, loft insulation, various construction products, animal feeds, horticulture and many other industrial applications. The cation exchange properties of vermiculite, and its layered structure and surface characteristics, are utilised in products such as intumescent coatings and gaskets, and the treatment of toxic wastes. The airfreight packaging of hazardous good is an increasing use of exfoliated vermiculite.

Safe and easy to handle, exfoliated vermiculite from is available in five different standard sizes as shown below; Dupré Vermiculite can also supply non-standard material for specific customer requirements. Ground or Micronised vermiculite powders can also be supplied.

Standard Grades - Typical Particle Size Distribution and Density: