Calcium carbonate is critical to the construction industry, both as a building material in its own right (e.g. marble), and as an ingredient of cement.  It contributes to the making of mortar used in bonding bricks, concrete blocks, stones, roofing shingles, rubber compounds, and tiles.  Calcium carbonate decomposes to form carbon dioxide and lime, an important material in making steel, glass, and paper.  Because of its antacid properties, calcium carbonate is used in industrial settings to neutralize acidic conditions in both soil and water.