Argentiferous galena, sphalerite, chalcopyrite, pyrite, and quartz occur in permeable zones at intersections of faults with favorable limestone beds. The primary sulfide zone is overlain by a silver-enriched intermediate zone (300- to 360-level) characterized by sulfides, cerussite, smithsonite, and subordinate anglesite and wulfenite. The ore of the enriched zone contains an average of 13 percent Zn and 13 oz Ag per ton. Silver increases downward, and the Zn:Pb ratio increases downward to a value of 0.6. The oxidized and leached zone contains remnants of sulfides, cerussite, anglesite, and wulfenite. Zinc and silver values are low. The behavior and sequence of individual minerals varies within zones.

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