Grout can be formulated from a variety of cements and minerals and proportioned for specificapplications. Neat cement grout refers to formulations without aggregate, containing only hydraulic cement, water, and possibly admixtures. Sanded grout is any mix containing fine aggregate and it is formulated much like masonry mortar. Whether neat or sanded, cementitious grouts derive their strength and other properties from the same calcium silicate-based binding chemistry as concrete.