Production of Portland cement from chalk and clay uses much less energy than production of an equal volume of plastics and metals. Natural polymers - organic materials such as rubber - have been supeseded by synthetics, almost all made from petroleum. Some Structures are shown. These burn. Inorganic materials would not burn. New inorganic materials such as aluminium phosphate glass and Macro-Defect-Free cement (MDF) are tough because their pores are minute. Methods of manufacture of transparent glass at 100°C are described. SEM photos of abalone shell and foamed vermiculate.