diatomite

mineral

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July 23, 2026

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Diatomite, also known as diatomaceous earth, is a light-colored, porous sedimentary rock composed of the siliceous shells of diatoms. Diatoms are microscopic, unicellular aquatic plants. This material resembles chalk but is much lighter and does not effervesce in acid.123

Diatomite has numerous industrial applications, including filtration for various liquids like sugar, syrups, oils, and beverages. It is also used as a filler in products such as paper, paint, and ceramics. Additionally, it serves as an effective insulator for high temperatures and is used as a mild abrasive in polishes and toothpaste. Major deposits are found in California, USA, as well as in Denmark, France, and Russia.1

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algae
Ecological and commercial importance
…their fossilized remains are called diatomite. Diatomite contains approximately 3,000 diatom frustules per cubic millimetre (50 million diatom frustules per cubic inch). When geologic uplifting brings deposits of diatomite above sea level, the diatomite is easily mined. A deposit located in Lompoc, California, U.S., for example, covers 13 square kilometres…
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…their fossilized remains are called diatomite. Diatomite contains approximately 3,000 diatom frustules per cubic millimetre (50 million diatom frustules per cubic inch). When geologic uplifting brings deposits of diatomite above sea level, the diatomite is easily mined. A deposit located in Lompoc, California, U.S., for example, covers 13 square kilometres…
Read More

diatomaceous earth
…well hardened, it is called diatomite. Similar siliceous rocks, called radiolarian earth and radiolarite, are formed from the latticelike opaline skeletons of Radiolaria.
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…well hardened, it is called diatomite. Similar siliceous rocks, called radiolarian earth and radiolarite, are formed from the latticelike opaline skeletons of Radiolaria.
Read More