Calcium silicate applies to a number of related compounds consisting of calcium, silicon, and oxygen, all of which tend to occur in a hydrated form.The calcium silicates have a number of uses in industry. Among the most important applications are their uses in building materials, such as some types of glass and cement (especially Portland cement), bricks and tiles for roofs, fireproof ceilings, and building boards. The compound is also used as a filler in the manufacture of paper and some types of plastics, where it gives body to the final product.