Vermiculite is the geological name given to a group of hydrated laminar industrial minerals, which are all aluminium-iron magnesium silicates, resembling muscovite (mica) in appearance. When subjected to heat, vermiculite has the unusual characteristic of exfoliating, or "popping up" due to the interlaminar generation of steam. The following specifications relate to the vermiculite mined at the Loolekop deposit in the North-Eastern Transvaal.

Vermiculite grade PLV-150 is a pure vermiculite, specially processed by proprietary techniques to impart to the product unique chemical-physical properties. It is light biscuit-brown (resembling bentonite) in colour. The "feel" of the product is slightly "oily". This is due to the fact that the fine lamelae "glide" over each other. This characteristic gives it exceptional reinforcement, slip and other related properties, all of which are used in various applications in industry.