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about Wollastonite

■ Wollastonite(CaSiO3)

WollastoniteWollastonite(calcium silicate, CaSiO3) is a naturally occuring glossy white or grey non-metallic mineral with an acicular or needle-shaped crystal structure in skarns and is developed in contact between limestone and granite.

This distinctive property makes wollastonite an ideal performance mineral for a wide range of industrial and consumer applications.
Because of its unique cleavage properties, wollastonite beneficiates into needle-shaped particles of varying acicularity(i.e. length of the particle is greater than its diameter, also known as aspect ratio) which KANSAI MATEC controls with its leading-edge pulverizing and separating technology.

Crystal from WOLLASTNITE.


The brightness and whiteness of wollastonite also enhance its use for certain filler and ceramic applications.
Finally, wollastonite is completely inert and non-carcinogenic with low biodurability, and its dusts are biosoluble; qualities that have made it a recognized substitute for short-fiber asbestos and many man-made fibers.
With complete control of the mining, milling and classification process at our own advanced facilities , we can provide wollastonite products such as normal grade(long fiber and short fiber filler)and fine grade(powdered filler) with good stable quality.

General Property of Wollastonite,

Specific gravity 2.80 - 2.95
Melting point(℃) round 1,500
Hardness(mohs') 4.5 - 5.0
Crystal form triclinic
Solubility 0.0095(g/100ml)
pH(10%slurrying) 9.5 - 10.5
Refractive index 1.63
Coefficient of expansion 6.5x106(㎜/㎜/℃)
Aspect ratio 3 - 20

Safety of Wollastonite

Carcinogenic classification of IARC

Classification Content Material
Group 1 The agent is carcinogenic to humans. Asbestos, Benzene etc.
Group 2A The agent is probably carcinogenic to humans. Ultraviolet rays etc.
Group 2B The agent is possibly carcinogenic to humans. Weld fume, ceramic fibers etc.
Group 3 The agent is not classifiable as to its carcinogenic to humans. Wollastonite, Rock wool etc.
Group 4 The agent is probably not carcinogenic to humans. Caprolactone etc.

31 Mar.2014

Wollastonite sources

Wollastonite sources Small scale of wollastonite deposits are occurred in the contact between limestone and granite in Japan.
Main sources of wollastonite are China, USA, Mexico, India and Finland.