Wollastonite for ceramics

Imerys wollastonites are excellent, cost-effective natural fluxing agents and frits for traditional ceramics such as floor and wall tiles, large surfaces, sanitaryware and tableware.

Why use wollastonite in ceramic bodies, glazes and engobes

Wollastonite is a multifunctional ceramic mineral used as a reinforcing agent and natural flux in ceramic bodies, glazes and engobes. It improves strength, reduces firing shrinkage, lowers vitrification temperature and enhances glaze finish, making it an ideal replacement for calcium carbonate in traditional ceramic formulations.

Wollastonite is characterized by:

• Acicular particle structure
• Calcium metasilicate chemistry (CaSiO₃)
• Consistent low loss on ignition (<1%)

Benefits of wollastonite in ceramic green bodies

Mechanical reinforcement and shrinkage control

• Reduces firing shrinkage
• Increases green and fired toughness
• Enhances impact strength

Thermal and drying performance 

• Improves thermal shock resistance
• Speeds up drying times
• Lowers firing temperatures and cycles

Wollastonite contributes calcium oxide without releasing CO₂ during firing, reducing outgassing and glaze defects.

Benefits of wollastonite in ceramic glazes

Glaze surface quality and defect reduction

• Reduces pinholes
• Eliminates glaze crazing
• Prevents cracking
• Improves smoothness and transparency

Fluxing and thermal expansion control

• Lower vitrification temperature
• Reduce thermal expansion
• Maintain brightness during firing

Replacing Calcium carbonate (GCC) with wollastonite in sanitary glazes can eliminate glaze crazing while improving thermal compatibility between body and glaze.

Benefits of wollastonite in engobes

Opacity & surface control

• Improves whiteness
• Lower opacifier demand
• Prevent crawling (drying cracks)
• Reduce thermal expansion

Sustainable ceramic manufacturing with wollastonite

Imerys wollastonites offer more than just technical advantages in ceramics processes; they also provide numerous sustainability benefits, such as:

• Lower firing temperatures
• Reduced kiln cycles
• Lower CO₂ emissions compared to traditional materials
• Improved energy efficiency
• Cleaner kiln atmosphere

Imerys produces wollastonite in the United States and Mexico

Imerys mines and processes wollastonite in North America, ensuring secure regional and global supply to Europe and Asia Pacific, as well as consistent mineralogy and technical support for ceramic manufacturers across the Americas and worldwide.

• Willsboro, New York, USA
• Hermosillo, Mexico
• North America supply security
• Consistent purity and low LOI

Choosing the right wollastonite grade

We offer a wide range of wollastonites to suit your particular requirements.  

Contact us to select the right grade for your process requirements