Ore petrology / Рудная петрология

This book is concerned with the study of ores as rocks—that is, with ore petrology. 
For much of the last three hundred years—and certainly for much of the twentieth century—most students of ore genesis have regarded the majority of metalliferous deposits as exotic entities, derived from extraneous sources and superimposed on geological situations to which they bore little or no genetic relationship. Almost the only exceptions have been those, such as ores of chromium and nickel, that have apparently formed as part of the igneous rocks that enclose them. From time to time it has been suggested that at least some other ore types, such as disseminated sulfides in black shales, might be “rocks in their own right,” but these views have usually been submerged by those involving introduction from elsewhere. Belief in a general exotic origin was natural when mining technologies were crude, since under these circumstances only rich vein fillings merited the term ore. With the more recent refinement of mining and concentrating techniques, however, vein fillings have lost their preeminence, and a wide variety of materials now attract attention as potential sources of metal. While the minerals of veins are undoubtedly introduced, those of many of these other rock bodies are by no means of such clearly foreign origin. This has led to the suspicion and, in some cases, the conviction—that in many instances the ore minerals concerned are an original, primary part of the rock formation in which they occur and hence that ore genesis and rock genesis are one and the same thing. This book is written with the latter possibility very much in mind: that ores as a class are divisible into ore types, that each ore type is a part of a particular netrological association, and that a fundamental consideration in genetic studies is geological environment. <...>