What Is the Main Ingredient in Cement?

A single, predominant ingredient cannot be chosen from cement mixture materials. Cement is made from a blend of ingredients including calcium, silicon, aluminum and iron.

The ingredients of cement include limestone, shells and chalk combined with shale, slate, clay, silica sand, blast furnace slag and iron ore. These ingredients are heated at high temperatures to form a rock-like substance, which is then ground into cement powder.

Portland cement is the material used to form concrete. When mixed with water, it forms a paste that binds with sand and rock that hardens into concrete. Portland cement was invented in the early 19th century by a bricklayer in Leeds, England, who created the cement by burning powdered limestone and clay in his kitchen oven.