Welcome to Imerys Performance Minerals


What is chamotte?

Imerys chamotte

Chamotte—also known as ‘grog’ and ‘firesand’—is calcined clay containing a high proportion of silica and alumina. It is produced by firing selected fire clays in a rotary kiln to temperatures between 1,400°C and 1,600°C, before grinding and screening to specific particle sizes.


Typical chamotte contains 40% minimum alumina, 30% minimum silica, 4% maximum iron oxide, and up to 2% calcium oxide and magnesium oxide combined. The particle size distribution is generally coarser in size than other raw materials used to prepare clay bodies.

Physical properties

  • Low porosity

  • High density

  • Excellent thermal stability

  • Excellent thermal shock resistance

  • High mechanical resistance

  • Corrosion resistance

  • Ceramics
  • Kiln furniture
  • Ceramics

    • In the production of sanitaryware pieces, Imerys chamottes are used to produce fine fire-clays which act like a skeleton, enabling the production of large, complex pieces such as baths and shower trays with enhanced mechanical properties. Fine fire-clays are more suited to the production of large, more sophisticated designs than vitreous ceramics. 
    • The tile industry also uses chamottes, particularly for the production of extruded tiles.
  • Kiln furniture

    Cordierite-chamotte materials are the main constituents of high thermal shock resistant kiln furniture.

    Imerys chamotte kiln furniture

For more information, please visit Imerys Ceramics.