Cristobalite is a high-temperature modification of quartz. Unlike quartz, it occurs only very rarely in nature. For this reason, cristobalite for industrial uses is manufactured synthetically by subjecting pure quartz to temperatures of approx. 1500°C in a rotary kiln. Calcination produces a jointed grain surface, a high degree of whiteness and a reduction in density to 2.35 g/cm3. Cristobalite, like quartz, is chemically inert. Using a combination of iron-free grinding and optical technologies, Quarzwerke is capable of producing highly refined cristobalite powders with particle sizes of 1μm.
Features
• High degree of whiteness (Y > 94)
• Hardness of 6.5 (Mohs)
• High chemical resistance
• Low density 2.35 g/cm3
• Jointed surface
• Thermal expansion coefficient: 54*10-6 K-1(at temperatures of 20-300°C)
• Good thermal conductivity: 8 W/m*K
Key applications
• Dispersion-binding exterior paints and plasters
• Compounds for dental casts
• Sanitary fixtures made of PMMA, UP
• Silicon sealing compounds
• Anti-blocking in PP and PE films
• Road markings