Kieselguhr was formed from the silicic acid‐containing skeletons of microscopically small water plants, deposited on the floor of oceans and seas several hundred thousand years ago. Due to its extremely porous structure and large internal surface, kieselguhr is highly suitable for various filtration purposes. Visually, the fine product types can be identified by the pink colour, whilst medium‐fine and coarser types are white in colour.