The Mining Magazine, Vol. 10

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Excerpt from The Mining Magazine, Vol. 10: January to June, 1914 The St. John del Rey, in Minas Geraes, Brazil, is one of the heroes of mining. This mine has survived two cavings or collapses of its workings, and has continued to grow deeper with unexampled pertinacity. Started in 1834, the upper workings collapsed in 1867, and again in 1886. Two new shafts were started in 1887, and completed in 1892 to the bottom of the mine, then at 2264 feet, in 1895. A cautious policy, due to the ¿at dip of the lode and the weakness of the hanging wall, has prevented the company from developing the mine on a grand scale, instead, the lower workings consist of a step-like series of levels and Shafts, each Shaft, 900 feet deep, being 1000 feet farther west than its predeces sor, with which it is connected by a main level. The mine is now 7300 feet deep on the dip, and 5200 feet vertically. Since 1835 the total yield has a value of Since 1895, when Mr. George Chalmers re~opened the mine on a new scheme of development, to the end of 1913, the yield of gold has been ounces worth from long tons of ore. The orebody has averaged 600 feet in length, and 45 feet in width. No marked impoverishment has been evident in the last two thousand feet of sink ing, although the orebody is longer and less wide, indeed the St. John del Rey is the rare exception of persistence of ore in depth. The December figures are not yet to hand but the output for 1913 may be estimated at long tons, yielding ounces. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This 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.