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Wall-Rock Alteration
April 2004 by Edgar B. Heylmun, PhD
Wall-rock (country rock) alteration is found in all hard-rock mining districts and has been caused by hydrothermal solutions in the past history of the region. The zones of alteration have a bearing on where one might drill for ore bodies. The weekend prospector does not have the tools nor knowledge to block out ore deposits, but he can narrow down his search dramatically by understanding the zones of wall-rock alteration that he sees.Alaska: Large-Scale Mining Can Be Done Right
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43 CFR 3809 Final Rule

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