Bentonite clay and diatomaceous earth are naturally occurring micro-particle materials in the United States. Though they do not sound common, they are found in many different products and serve many purposes in everyday life. For example, diatomaceous earth is a common component in pool filtration systems, while bentonite clay is used in cat litter.

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Diatomaceous earth is used in the filtration system for swimming pools.

Diatomaceous Earth: Identification

Diatomaceous earth, or DE, is the name given to a product made from unicellular algae, or diatoms, according to Princeton University. The cell walls of these algae consist of silica, but the walls can vary in shape based on the type of diatom: centric or pennate. Centric diatoms have radial symmetry, while pennate diatoms are bilateral. In large numbers, these tiny fossilized algae create the dust known as DE.

Bentonite Clay: Identification

Bentonite clay falls into one of the four main groups of clay materials: smectite. Smectites are a group of clays that feature high swelling or shrinking potential. Bentonite clay is made up of micro-particles that consist of anionic smectite clay materials, better known as volcanic ash. It is common in the United States in areas such as Wyoming or in Kentucky, where it can be found in some areas as thick as 3 feet.

Diatomaceous Earth Uses

There are multiple forms of DE, including a food-grade version. Pool-grade DE is another form, used in the filtration systems of in-ground and above ground swimming pools in homes across the United States. Diatomaceous earth also plays a part in drinking water filtration systems, controlling and repelling insects and even for brewing beer.

Bentonite Clay Uses

Like DE, bentonite clay is also commonly found in many homes in the United States. Bentonite clay has swelling properties, making it ideal for use in cat litters. Unlike diatomaceous earth, bentonite clay does not allow water to filter through, making it ideal for sealing water features in landscaping or for preventing contamination of drilling fluids in rotary drilling muds. It can also be used in manufacturing situations, such as iron ore pelletizing.