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Product Benefits
Technical Details

Wollastonite (silicate, chemical formula CaSiO3) exists in an acicular and non-acicular form.

Wollastonite can be characterised by:


  • Shape (non-acicular/ acicular)
  • Medium Mohs hardness of 5
  • Alkaline nature.


Basic properties

Property F/ FG G Unit
Moisture < 0.2 0.2 [%]
pH 10 [-]
Hardness (Mohs) 5 [-]
Refractive index 1.63 [-]
L.O.I. 3.5 n.d. [%]
Density 2.9 [kg/ dm3]






Product overview

Product Grade D50



[g/ 100 g]

Casiflux FG20 18 54 94
F75 28 59 90
G20 10.5 30 96
G38 18 28 96


Production locations Casiflux


Casiflux is the brand name for Sibelco’s wollastonite products.

  • Acicular grades are named Casiflux F or Casiflux FG
  • Granular grades are named Casiflux G





  • Mud cracking resistance: due to its acicular shape, wollastonite will form a physical network inside the coating which reinforces the coating and, as a result, lowers the tendency for cracking.
  • Chemical resistance: wollastonite has a synergistic effect with dedicated anti-corrosive pigments, such as zinc phosphates.
  • Mechanical reinforcement: due to its acicular structure, wollastonite will mechanically reinforce the binder matrix.
  • Abrasion resistance: due to its hardness of 5 on Mohs scale, wollastonite will increase the coating’s resistance to wear.
  • Rheology control: due to its acicular shape, wollastonite has an impact on the rheology profile. When applying shear, the acicular particles will align and provide a low viscosity. When shear is removed, the acicular particles lose their orientation and cause the viscosity to increase above the level expected when the particles had a non-acicular shape.


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