Vermiculite is an entirely and naturally occurring mineral, similar to mica, that is sold both in its natural state and by exfoliating the core. Exfoliation is the term used to describe the expanding process raw vermiculite goes through under extreme heat, rendering the material naturally layered, perfectly suited for trapping air and moisture. It does not create any waste by products during processing and is inert, non-toxic, fire resistant and is capable of holding many times its weight in water.