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Major and minor elements in bulk rocks are due to occurrence of mostly quartz, ankerite, illite and minor pyrite. Silicification forms megaquartz by dissolution and replacement of carbonates. Illite is unaffected during ankerite formation. Gold mineralization is unrelated to quartz, illite and pyrite contents. Gold mineralization is related to ankerite formation because gold content increases with increasing ankerite values.
Gold mineralization occurred in a reducing burial environment. Fe in solution was high due to alteration of ultramafics and leaching of clay minerals during silicification. During silicification fluids were acidic and as these solutions progressively dissolved and replaced carbonate, the alkalinity of fluids increased and formed ankerite. In alkaline conditions, gold precipitated along with ankerite.