Sodium metasilicate, also known as water glass, is an inorganic substance with the chemical formula Na₂SiO₃. It is available in colorless, greenish, or brown solid or viscous liquid forms. Widely used in foundry, papermaking, sand casting, pattern making, paper tube and box adhesives, construction, carbon black, subway construction, gold and silver foil lamination, ceramics, alkaline silicate, and more. Various liquid sodium metasilicate products can also be customized according to customer requirements.