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Beskrivelse
Mining historian Kerby Jackson introduces us to a classic mining publication on ore sampling from the U.S. Bureau of Mines. First published in 1916, it has been unavailable for over a century and sheds important light on historic methods of ore sampling in hardrock mines. Topics include how to take correct ore samples and the conditions that affect sampling, such as their subdivision and uniformity. Particular detail is given to methods of hand sampling ore bodies by grab sample, pipe sample and coning, as well as sampling by mechanical methods. Also given are insights into the screening, drying and grinding processes to achieve the most consistent sample results and much more. This hard to find information is a must for those interested in small scale gold mining or in historic mining methods. Note: This edition is a perfect facsimile of the original edition and is not set in a modern typeface. As such, some type characters and images might suffer from slight imperfections or minor shadows in the page background.