Calcined clay, also known as metakaolin, is a pozzolanic material that is produced by heating natural clay at a high temperature to transform its mineral composition.

Calcined clay (metakaolin) finds important applications in the mineral formulation and tile/sanitaryware segments of the ceramics industry.

Here’s how it is utilized in these areas:

1. Mineral Formulation:

Ceramic Glazes and Bodies:

• Calcined clay is used as a component in ceramic glazes and bodies to enhance various properties such as color development, surface finish, and mechanical strength.
• It can also contribute to controlling the thermal expansion of ceramics.

Stain and Pigment Production:

• Metakaolin can be used in the production of ceramic stains and pigments.
• Its controlled mineral composition can influence the color and stability of these additives.

Ceramic Additives:

• Calcined clay can be used as an additive to modify the properties of ceramic formulations.
• It can influence the firing behavior, shrinkage, and porosity of the final ceramic product.

2. Tile and Sanitaryware Segment:

Tile Body Composition:

• In the production of ceramic tiles, calcined clay can be included in the tile body formulation to enhance its properties.
• It can improve the strength, reduce porosity, and provide better firing behavior, leading to high-quality tiles.

Glaze Formulation:

• Metakaolin is used in glaze formulations to improve the adhesion of glazes to tile surfaces.
• It also contributes to achieving the desired texture, appearance, and glossiness of the glaze layer.

Sanitaryware Production:

• In the manufacturing of sanitaryware products like toilets and sinks, calcined clay can be utilized to enhance the performance and aesthetics.
• It can contribute to the strength and durability of the sanitaryware items.
• Color Control: Metakaolin’s consistent mineral composition makes it a useful ingredient for achieving consistent colors in ceramic products, including tiles and sanitaryware.

Surface Finish Enhancement:

• Adding calcined clay to ceramic formulations can result in smoother and more refined surfaces on tiles and sanitaryware items, improving their overall visual appeal.

• Dimensional Stability: The use of calcined clay can contribute to reducing dimensional changes during firing, which is crucial for maintaining the accurate sizing of ceramic products.