Gold is a trace constituent (average 0.015 ounces per ton) in the matrix of virtually all the 28 conglomerate beds exposed at the mine, and economic concentrations occur in 10 beds that are interpreted as giant foreset beds. The greatest concentrations occur close to the line where the foresets grade into topsets, supporting a placer origin for the gold. During subsequent folding, metamorphism, and intrusion, gold was redistributed to form concentrations at the top of the conglomerate beds and near dike contacts. Some gold is seen in fractures cutting conglomerate boulders. High-grade gold is associated with stringers of pitchblende. There is no evidence that gold is necessarily cogenetic with pyrite or uranium minerals.

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