Palygorskite

Palygorskite is a rare fibrous clay mineral with the chemical formula (Mg,Al)2Si4O10(OH)·4H2O. It is also known by the trade name attapulgite. This mineral is characterized by its needle-like or acicular crystals that can be arranged in bundles or felted masses. Palygorskite is typically white to grayish or greenish in color and has a soft, earthy feel. It is formed through the alteration of other magnesium-rich minerals, such as pyroxenes and amphiboles, in arid or semi-arid environments, often associated with evaporite deposits.

The unique fibrous structure of palygorskite gives it a high surface area and porosity, which are responsible for its notable adsorptive properties. These properties make it useful in various industrial applications. It is commonly used as an absorbent for oils and greases, a decolorizing agent for edible oils, a filler in paints and plastics, and a carrier for pesticides and herbicides. In some regions, palygorskite has also been historically used as a source of pigment or even as a component in construction materials. Its presence can be found in sedimentary rocks worldwide, but economically significant deposits are less common.