Calcium silicate, otherwise known as slag, has a low bulk density and high physical water absorption. It is used as an anti-caking agent and an antacid. A white free-flowing powder derived from limestone and diatomaceous earth. Calcium silicate has no known adverse effects to health. It is used in roads, insulation and roof tiles.

Calcium silicate in the steel industry

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It is also the remains of when molten iron is made from iron ore and calcium carbonate to produce slag in a blast furnace. CaSiO₃

Silicates | Calcium compounds | Metallurgy