kaolinite

American  

[key-uh-luh-nahyt] / ˈkeɪ ə ləˌnaɪt /

noun

1. a very common mineral, hydrated aluminum disilicate, Al 2 Si 2 O 5 (OH) 4 , formed by the alteration of other minerals, especially feldspar: the most common constituent of kaolin.

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kaolinite British  

/ ˈkeɪəlɪˌnaɪt /

noun

1. a white or grey clay mineral consisting of hydrated aluminium silicate in triclinic crystalline form, the main constituent of kaolin. Formula: Al 2 Si 2 O 5 (OH) 4

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kaolinite Scientific  

/ kā′ə-lĭ-nīt′ /

1. A soft, white triclinic mineral occurring in friable masses. Kaolinite forms as the result of the hydrothermal alteration or weathering of feldspar. It is used in the ceramic industry. Chemical formula : Al ₂ Si ₂ O ₅ (OH) ₄ .

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Etymology

Origin of kaolinite

First recorded in 1865–70; kaolin + -ite ¹

Example Sentences

On Earth, kaolinite forms only after rocks and sediments are stripped of most other minerals through prolonged exposure to water.

From Science Daily • Jan. 27, 2026

NASA's Perseverance rover identified the rocks as kaolinite clay, a white, aluminum-rich material.

From Science Daily • Jan. 27, 2026

With time, as the soft tissue decayed, a white-colored clay mineral called kaolinite filled the void left by the brain.

From New York Times • Aug. 18, 2021

It’s made from the chalk mineral kaolinite, refined to exclude impurities and micronize the particles to a finer texture that’s ­sprayable and disturbing enough to drive the beetles away.

From Washington Post • Apr. 25, 2017

These include the clay minerals kaolinite, illite, and smectite, and although they are difficult to study because of their very small size, they are extremely important components of rocks and especially of soils.

From Textbooks • Jan. 1, 2015