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This chapter focuses on S in porphyry-type ore deposits, layered-mafic-intrusion-hosted ore bodies, and magmatic sulfide deposits. Porphyry-type ore deposits, e.g., Bingham Canyon, Utah, U.S.A. and Grasberg, Irian Jaya, are important hosts of Cu, Mo, Au, and Ag. Ore deposits hosted in layered mafic intrusions, e.g., the Bushveld and Stillwater complexes, contain significant quantities of Ni, Cu, Cr, Au and the platinum group elements (PGE: Pt, Pd, Rh, Re, Ir, Ru). Magmatic sulfide deposits, differentiated from layered mafic intrusions in that the former evince more clearly a role for immiscible sulfide accumulation without the possible presence of an aqueous fluid(s), e.g., Noril’sk and Voisey’s Bay, contain significant quantities of Cu, Ni, and the PGE. Allowing for some variability within any given ore deposit type, each of these types is unique in terms of the range of pressure and temperature of ore deposit formation, tectonic setting, and the compositional type(s) of parental causative magma. However, most porphyry-type ore deposits, layered-mafic-intrusion-hosted ore bodies, and magmatic sulfide deposits share the following features: 1) they are related chemically and physically to silicate magma; 2) they are the byproduct of differentiation of magma; 3) metals are hosted dominantly in sulfide minerals and the deposits can be thought of primarily as S anomalies (e.g., the Butte and Bingham Canyon porphyry ore deposits, located in Montana and Utah, U.S.A., respectively, contain 60 and 100 times, respectively, the ~20 Mt of S emitted during the 1991 eruption of Mt. Pinatubo); and 4) the metal(s) and S in each deposit type, albeit not necessarily the total quantity of S, are together derived from the same magmatic source. It is the connectivity of these commonalities that serves as the basis for this review chapter.
The ubiquitous presence of S in magmatic systems is manifested in the commonly observed mass of S …