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Experiments have been conducted at 200MPa, 800–1030°C, and fO₂ 0.8 log units below the Ni–NiO buffer to determine the solubility of Au, Cu and Ag in silicate melts and pyrrhotite. The metal activities were imposed by using Au₉₆₅Ag₀₂₀Cu₀₁₅ alloy capsules. Sulfur-free and sulfur-bearing systems were studied with otherwise identical melt compositions to assess the relative effect of S on the solubility of these metals. The data show that the major element composition of the silicate melt only moderately affects the solubility of Au, Ag and Cu between basalt and dacite, yielding solubilities identical within 50% relative. In comparison, solubilities in the rhyolite melts are lower by a factor of 1.5–2.5 for Cu and higher by up to a factor of 5 for Ag, depending on the aluminum saturation index of the melt. The solubilitiy of Ag significantly increases with increasing peraluminousity above an aluminum saturation index of 1 …