Vermiculite, a phyllosilicate group mineral, is basically a hydrated phlogopite mica, which expands - exfoliates - when heated. Being non-combustible and insoluble in water or organic solvents, vermiculite is safe and easy to handle, making it suitable for a wide range of applications ie animal feedstuffs, lightweight bituminous screeds, fire protection, friction linings, horticulture (growing ...