Cement Alternative Is 5x Stronger and Absorbs CO2

(via PBS Newshour) Cement has been called the foundation of modern civilization, the stuff of highways, bridges, sidewalks and buildings of all sizes. But its production comes with a huge carbon footprint. Environmental chemist David Stone was seeking a way to keep iron from rusting when he stumbled upon a possible substitute that requires significantly less energy. Special correspondent Kathleen McCleery reports.