Many individuals, even clients, use the terms “cement” and “concrete” interchangeably. In fact, the two are quite different, and one is involved in the making of the other. Cement is a fine powder made from a variety of ingredients such as limestone, aluminum, calcium, and others. The ingredients are heated in kilns to create clinkers, marble-like balls. Workers grind the clinkers into powder and add a mineral compound known as gypsum to give cement its gray, floury quality.
Concrete is a mixture of cement, water, and aggregate minerals, such as rocks or sand. The cement and water form a paste that binds the aggregates together, and the water kicks off the cement's hardening process. This occurs slowly, giving workers enough time to pour the concrete mixture into a mold if they need to create a certain shape. In many cases, cement comprises only 10 to 15 percent of a concrete mixture.