Diatomaceous earth, or DE as it is called, is found in various dry lake bed deposits which were formed anciently from the skeletons of millions of microscopic diatoms as they died and fell to the bottom of the lake or sea bed.
Diatomaceous earth is used in a wide range of industrial applications.
Because it absorbs moisture, it is dried and used as a dessicant in packaging. It is used in swimming pool filters and home water filters. It is widely used as an anticaking agent in prepared feed mixes, which has the added benefit of parasite control in the animals which eat the feed. The action upon parasites is entirely mechanical. The tiny particles of diatomaceous earth have spiny structures.