Material resources metals

Material resources often have controlled a nation s rise—and fall. Ancient Egypt developed bronze from its copper and tin, and weapons therefrom enabled it to dominate its sphere when copper ran out, Egypt succumbed. Similarly a silver mine gave Athens this noble metal for trading with its exhaustion Athens deteriorated. Energy resources today are equally important to national attainments, although the world s economics and politics now are very much more complicated than those of the ancients. 

Materials are precious resources of a country. Our material resources of iron, aluminum, copper, chromium, manganese, titanium, etc. are dwindling fast. Some day there will be an acute shortage of these materials. An impending metal crisis does not seem... 

A rather impressive Hst of materials and products are made from renewable resources. For example, per capita consumption of wood is twice that of all metals combined. The ceUulosic fibers, rayon and cellulose acetate, are among the oldest and stiU relatively popular textile fibers and plastics. Soy and other oilseeds, including the cereals, are refined into important commodities such as starch, protein, oil, and their derivatives. The naval stores, turpentine, pine oil, and resin, are stiU important although their sources are changing from the traditional gum and pine stumps to tall oil recovered from pulping. 

As humans entered the Bronze Age, charcoal was the only material that could simultaneously heat and reduce metallic ores. Later, the addition of an air blower made it possible to achieve temperatures high enough to soften or melt iron. During the Industrial Revolution, charcoal was largely displaced in most ironworks by coke derived from coal. However in Brazil, which lacks adequate coking coal resources, most of the charcoal produced is still used to reduce iron ore. 

It has been a long way from early synthetic polymers created as artificial substitutes (Kunststoffe) for scarcening metal resources, to modem materials tailormade to fill specific functions through particular properties and processing characteristics in many areas of application. Ever since they were first prepared, surprising new or improved properties have been discovered or engineered. 

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