Cristobalite is a high-temperature modification of quartz and, in contrast to quartz, its occurrence in nature is very seldom. For this reason, cristobalite is synthetically produced for industrial purposes from pure quartz in a rotary kiln at a temperature of approx. 1,500°C. A fractured grain surface, a high degree of whiteness and a density reduction to 2.35 g/cm3 is achieved by the calcination. Like quartz, cristobalite is chemically inert and is therefore popular as a filler in a variety of processes and products.
Properties
- hardness of 6.5 (Mohs)
- low density of 2.35 g/cm³
- high degree of whiteness (colour value Y > 94)
- high chemical resistance
- fractured surface
- thermal coefficient of expansion: 54*10-6K-1 (at a temp. of 20–300°C)
Main applications
- emulsion-bound exterior paints and renders
- dental impression composites
- engineered stone made from PMMA, UP
- silicone sealant compounds
- anti-blocking additive in PP and PE film
- road markings
Through non-ferrous milling and screening processes Quarzwerke is in a position of being able to make micronized cristobalite powders with a medium granularity of up to 1 µm.
Our cristobalite flours and powders are available uncoated under the trade name SIKRON®. The silanised types are available under the trade name SILBOND®.
We can therefore guarantee that we have the optimal solution for your application!