Iron Ores; Their Occurrence, Valuation and Control

IRON ORES - 1914 - PREFACE - The material presented in this volume has been worked over, at intervals, during many years of professional activity and certain sections have, as later noted, been published in various technical journals and in private and official reports. The volume as it now stands r [...]
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IRON ORES - 1914 - PREFACE - The material presented in this volume has been worked over, at intervals, during many years of professional activity and certain sections have, as later noted, been published in various technical journals and in private and official reports. The volume as it now stands represents an attempt to discuss iron ores not merely in their geologic and technical relations, but in their more general relations to industrial conditions. The field thus outlined is broad, and the risk of failure is correspondingly great. But on the other hand there havc bcen exceptional opportunities for studying thc iron-ore situation from several widely different standpoints, and something more than a purely technical treatment seemed to be both justified and desirable. The industries based upon iron ores arc of interest, directly or indirectly, to the entire business and financial world and have also to some degree become matters of political concern. Any adequate discussion of the general iron-ore situation must therefore take into consideration many factors not commonly regarded by the geologist or the engineer, and too often passed by as not susceptible of exact definition or scientific treatment. It is hoped that this volume will prove to be, if not conclusive, at least suggestive in these regards. Beginning with some consideration of the natural abundance and wide distribution of iron, the manner in which this disseminated iron is concclltrated into workable ore deposits is discussed in considerable detail. It may be noted, in this connection, that the sedimentary ores are given space more nearly commensurate with their overwhelming importance than has been common practice. Thesecond section of the volun eis devoted to discussion of the various factors affecting the value of iron ores and the valuation of ore deposits. An introductory chapter surnmariees the basal factors concerned in these matters. This is followed by a discussion of prospecting or exploratory work, in which for the first time an attempt is made to indicate the manner in which theories of origin actually bear upon the examination of ore deposits. Following this are chapters on mining costs, concentrating possibilities, and furnace and mill requirements, so far as any of these matters bear upon the subject of ore valuation. Later chapters of this section treat of prices, markets and other financial aspects of the problem. Descriptions of the more important ore deposits of the world are contained in the third part of the hook. In preparing these descriptions, an attempt has been made to consider the deposits in the light of their present and possible industrial importance. Deposits of local importance and those which are of interest solely as geologic occurrences are not described, and individual mines and ore properties are not noted except as illustrating general types. The attempt has been to give, with regard to each important ore field, sufficient data concerning its location, type, ore grade, shipments and reserves to justify conclusions expressed by the writer, or to enable the reader to form his own conclusions, as to the present and possible future importance of that field. In most cases very full reference lists are included, so that further details can be looked up as desired...