Casting—along with molding and ramming—is the aggregation and consolidation of material within the physical confines of a mold or form. An additive procedure, casting is the opposite of carving but can produce similar stereotomic results. Because casting depends on the chemical transformation of a substance from a fluid to a solid state (ramming transforms granular materials into stable solid forms) it requires specific and precise knowledge of the make-up and behavior of the material in its liquid state; experience with its viscosity (resistance to flow); the optimum conditions for its solidification through curing, cooling, or drying; and the necessity and technique for introducing tensile reinforcement internal to the final form.