Ground calcium carbonate (GCC) is a chemical compound with the formula CaCO3. Calcium carbonate is the active ingredient in agricultural lime, and is created when calcium ions in hard water react with carbonate ions creating limescale. It is commonly used medicinally as a calcium supplement or as an antacid.
Precipitated calcium carbonate (PCC) is also a product derived from lime, which has many industrial applications. PCC is made by hydrating high-calcium quicklime and then reacting the resulting slurry, or “milk-of-lime”, with carbon dioxide. In the PCC process, products can be made with very small sizes, with high surface areas, high oil absorptions, and/or with different powder bulk densities— from ultra-low to super-high powder densities. The different shapes allow PCC to act as a functional additive in sealants, adhesives, plastics, rubber, inks, paper, pharmaceuticals, as well as nutritional supplements.