The Future of the Lake Superior District as an Iron-Ore Producer (Classic Reprint)

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Excerpt from The Future of the Lake Superior District as an Iron-Ore ProducerIt is, of course, recognized by everyone, that at some future date all of the merchantable ore will have been removed from the district. This date is placed by various estimators at from 15 to 30 years hence. This statement is based on the assumption that the present rate of shipment will continue until the end of the season of the last year. This, of course, can not be the case. The history of any successful mining district shows that during the first few years of life small tonnages of high - grade material are mined. As time passes and a district is more largely exploited, the tonnage mined each year increases. As the tonnage increases, the grade of the ore usually becomes lower. After a certain time, the yearly production of the district reaches a maximum and after the maximum is passed, the production gradually decreases. The rate of decrease in production is quite rapid at first, but absolute depletion of the district may not occur ior a great many years. The history of the Lake Superior district will, undoubtedly, follow in a general way the history of most mining districts, and it is to be expected that some day, past or future, the district has reached, or will reach, the peak of its production. After the peak is passed, and it becomes generally recognized that the district is on a de cline, the descent toward absolute depletion will be quite rapid.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.