Durable. Light. Stain-Resistant Concrete Products. NatureCast Concrete products are made of sand, water and cement. These are the same primary ingredients that have been used for centuries to make concrete structures; some of which are still intact and in use 2,000 years later. By combining advanced reinforcement technology with curing and construction design, NatureCast Concrete has twice the tensile strength of solid concrete, four times the bending strength of solid concrete, and reaches compression strengths of up to 11000 PSI.