This book is about minerals and mineral resources, about the role they play in the economies of the United States and other countries, and about the problems involved in obtaining adequate supplies of minerals. These problems are important, because civilization as we know it today is dependent on the availability of a wide range of mineral materials and on continuing supply of many of them in very large amounts. Mankind's use of minerals is very old, dating from some unknown time, perhaps tens of thousand of years ago. When recording of history began, in the fourth millennium B. C., minerals and mineral-derived materials were already being used extensively in many parts of the world, for building materials, for tools and utensils of many kinds, for weapon, and for ornamental and artistic purpose. As the subsequent centuries and millennia passed, knowledge of minerals and of the means of obtaining them and converting them to useful forms increased, and minerals came into ever-wider use. The use of minerals on a modern scale, how ever, stems from the industrial revolution, which began in the eighteenth century. Since that time, consumption of minerals has expanded in both scale and diversity. Expansion accelerated as the nineteenth century progressed. In the twentieth century, expansion has been succeeded by explosion in the rate of use. Since 1900, mankind has produced and consumed more minerals than during all preceding recorded history. There is a direct correlation between the advance of civilization and the growth of minerals use. During approximately 200 years of life as an independent nation, the United States has changed its economy from predominantly agricultural to highly industrial. The effect on the material well being of the average American have been dramatic. Through the use of machines made from minerals, his productivity has been prodigiously increased, and through the automobile and airplane so has his mobility. He has available a fantastic variety of manufactured goods. He can communicate almost instantly with his fellow human beings in many parts of the world. To relieve him from hard labor he has a variety of machines not just the machines of industry but an array of personal machines, from power mowers to snow blowers, dishwasher, washing machines, and dryers, and perhaps an electric pump to change the water in a private swimming pool. By acquiring such items as the electric carving knife and electric toothbrush, he can enlarge his inventory of personal machines to a ridiculous degree. This book is especially concerned with the mineral problems of the United States. We live in a period of great change in the nature and basis of the American economy and in the status of the United States as a world power. Part of the change is a deterioration in the mineral position of the United States, defined in terms of our ability to supply our needs for minerals from our own resources. Part of the change is change in our industrial structure, reducing our capacity for converting mineral raw materials into manufactured goods and, by the same token, reducing the diversity of our industrial economy. The enormous strength of America during the first decades after World War II lay not only in the volume of industrial production bit in the remarkable diversity and near completeness of American industry, which provided almost all the links of the chain of processes from extraction of mineral raw materials to their conversions into manufactured goods. The period 1940 to 1960 was, for the United States, a golden age, when it drew from its own and the world's resources an unparalleled supply of minerals and built an unparalleled industrial economy

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