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Digging mineral wealth from the ground dates to prehistoric times, but the arrival of industrial mining techniques, especially after the California Gold Rush, made mines deeper and more complex than ever before. As American industrial mining came of age, mining engineers turned …
Digging mineral wealth from the ground dates to prehistoric times, but the arrival of industrial mining techniques, especially after the California Gold Rush, made mines deeper and more complex than ever before. As American industrial mining came of age, mining engineers turned …