The color of kaolin is mainly influenced by its composition and impurity content. The common colors and their differences are as follows:

I. White kaolin

Color characteristics: Pure kaolin is usually white or nearly white. This kaolin has a high whiteness, and its natural whiteness can reach over 85%.

Composition and impurities: It is mainly composed of kaolinite with very low impurity content.

Application: widely used in papermaking, ceramics, coatings and other industries, it is an ideal raw material for producing high-grade ceramics, paper fillers and coatings.

II. Grayish white kaolin

Color characteristics: Because it contains a small amount of impurities, the color is slightly gray.

Composition and impurities: It may contain a small amount of metal oxides such as iron and titanium.

Application: Suitable for mid-range ceramics, paper making and coating industries.

III. Yellow-white kaolin

Color characteristics: Because it contains a small amount of organic matter or other impurities, the color is slightly yellow.

Composition and impurities: It may contain a small amount of impurities such as organic matter and iron.

Application: It can be used in mid-range ceramics, paper making and coating industries.

IV. Yellow-gray kaolin

Color characteristics: the color is yellow or gray.

Composition and impurities: The impurity content is high, which may contain more metal oxides such as iron and titanium.

Application: Mainly used for producing low-grade ceramics, bricks, castings and other products.

V. Dark gray or black kaolin

Color characteristics: dark color, usually dark gray to black.

Composition and impurities: It contains high organic matter, iron, titanium and other impurities.

Application: This kind of kaolin is usually used in refractories, casting and other industries.

VI. Red kaolin

Color characteristics: because it contains high iron oxide and copper, the color is red.

Composition and impurities: iron oxide content is high.

Application: Traditionally used for treating joint pain, but also used in ceramics, coatings and other industries.

VII. Green kaolin

Color characteristics: Because it contains iron ions (such as Fe), the color is light blue or light green.

Composition and impurities: containing iron ions.

Application: It can be used in ceramics, coatings and other industries.

VIII. Brown kaolin

Color characteristics: the color is brown.

Composition and impurities: It may contain manganese oxide.

Application: It can be used in ceramics, coatings and other industries.

IX. Summary

The color of kaolin is mainly affected by its composition and impurity content. White kaolin is usually used in high-grade products because of its high purity and whiteness. The darker kaolin is mostly used in refractory and casting industries.