Fused Zircon Mullite Grain/Powder, (Al2O3 + ZrO2 + SiO2)


A fused zircon mullite grain, high purity product produced in an electric arc furnace from Bayer alumina and zircon sand. It is composed of large needle-like mullite crystals containing co-precipitated monoclinic ZrO2.

Chemical Name:  Zirconia-mullite

Chemical Formula: Al2O3 + ZrO2 + SiO2


Zirconia mullite powder, Zirconia aluminum silicate, Al2O3 + ZrO2 + SiO2, Fused zirconia mullite grain/ powder (Al2O3  + ZrO2 + SiO2), zirconia mullite grain, zirconia mullite powder, zirconia-mullite

Chemical Properties:

Al2O3= 45.80%, ZrO2= 36.0% and SiO2= 17.50%

Physical Properties:

Various RF splits/granulations are available from 6/F to DC fines

Typical Applications:

Used in specialty product applications where high resistance to environmental corrosion and a low coefficient of thermal expansion are desirable properties. Applications include ceramic pressure casting tubes and refractory shapes requiring resistance to molten slag and molten glass.


Molecular Weight (g/mol.) 
Density (g/cm3) 
Specific Gravity3.56
Specific Heat @25°C (cal/g-°C) 
Melting Point (°C)1750-1800
Boiling Point (°C) 
Thermal Conductivity @20°C (cal/s-cm-°C)  
Mohs Hardness @20°C 
Colorgrey to yellow