Silicates are used in the manufacture of fire-resistant panels by binding together inert materials such as perlite, vermiculite or diatomaceous earth. The silicates add fire-resistant and intumescent properties. Calcium silicate wallboard and acoustic tiles are manufactured from liquid silicates by reacting with calcium salts.
In extruded brick and clay products, soluble silicate can reduce the force (power) required for extrusion, as well as decrease shrinkage on firing. The extrusion becomes less stiff, yet the moisture content is not increased and may even be reduced. Since silicate is inorganic, it remains distributed throughout the extrusion without migrating to the surface, and it has no deleterious effect on the color of the fired product. The addition of magnesium sulfate into the clay results in an antique-effect finish.
Powder or liquid silicates can be combined into dry products for use in grouting and caulking tiles.