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

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

From Science Daily • Jan. 27, 2026

Broz noted that kaolinite can also form through hydrothermal processes on Earth, where hot water alters rock underground.

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

On the weathered surface the feldspar has been altered to the chalky-looking clay mineral kaolinite.

From Textbooks • Jan. 1, 2015