Calcium silicate used as an anticaking agent in food preparation, including table salt and as an antacid. It is approved by the United Nations' FAO and WHO bodies as a safe food additive in a large variety of products. It has the E number reference E552. Calcium silicate is commonly used as a safe alternative to asbestos for high-temperature insulation materials. Industrial-grade piping and equipment insulation is often fabricated from calcium silicate. Its fabrication is a routine part of the curriculum for insulation apprentices. Calcium silicate competes in these realms against rockwool and proprietary insulation solids, such as perlite mixture and vermiculite
Synthetic magnesium silicate other monographs for Food Grade synthetic magnesium silicate specify a mole ratio of 2MgO:5SiO. The most common use for Food Grade synthetic magnesium silicate is as an active filter aid for adsorption of color, free fatty acids and other polar compounds from used frying oils. Various national and international regulations allow use of this material as an anti-caking agent in a wide variety of powdered foods. When used as a food additive, it is safe to ingest synthetic magnesium silicate. In 1990, the safety of synthetic magnesium silicate was reviewed by the Scientific Committee on Food (SCF) together with that