Introduction
Calcium carbonate (CaCO₃) plays a vital role in ceramic and tile manufacturing, serving as one of the most widely used raw materials in the industry. Its versatility, purity, and ability to enhance whiteness, strength, and surface finish make it indispensable for ceramic producers worldwide.
What Is Calcium Carbonate?
Calcium carbonate is a naturally occurring mineral found in limestone, chalk, and marble. When processed into fine powder, it becomes a key ingredient in ceramic formulations, acting as both a filler and a fluxing agent that supports the sintering process during firing.
Importance of Calcium Carbonate in Ceramic Formulation
1. Acts as a Source of Calcium Oxide
During firing, calcium carbonate decomposes into calcium oxide (CaO) and carbon dioxide (CO₂). The CaO reacts with other oxides to form compounds that strengthen the ceramic body and improve its thermal stability.
2. Enhances Whiteness and Opacity
High-purity calcium carbonate contributes to better color control and brightness in tiles and sanitaryware. Its fine particle size helps achieve smoother textures and a uniform surface finish.
3. Improves Sintering and Densification
As a flux, calcium carbonate lowers the melting point of the ceramic mix, promoting better particle bonding and reduced porosity, which results in durable, dense tiles.
4. Balances Shrinkage and Hardness
The correct ratio of calcium carbonate ensures dimensional stability, minimizing warping or cracking during firing while maintaining high mechanical strength.
Role in Glaze Production
In glaze formulations, calcium carbonate acts as a flux material, promoting the fusion of silica and alumina. It improves gloss, transparency, and smoothness, producing the brilliant finishes seen on modern ceramic tiles.
Applications in the Industry
- Floor and wall tiles
- Porcelain and sanitaryware
- Roofing ceramics
- Decorative pottery
- Industrial ceramics
Choosing the Right Calcium Carbonate
Manufacturers should consider:
- Purity: >98% CaCO₃ for optimal performance
- Particle size: Microfine powder (1–5 µm) for glazes; coarser grades for bodies
- Brightness: Above 95% for light-colored ceramics
- Moisture content: Below 0.2% for stable mixing
Conclusion
Calcium carbonate remains a cornerstone mineral in ceramic and tile production — improving quality, efficiency, and aesthetics. For producers aiming to achieve consistent color, hardness, and gloss, premium-grade calcium carbonate is a key ingredient that delivers measurable results.
