This grant provides support to Ed Ripley and a graduate student at the University of Indiana to conduct stable isotopic, trace elemental and compositional analysis of rocks associated with the Voisey's Bay massive sulfide deposit in Labrador, Canada. The Voisey's Bay deposit is one of the largest economically viable nickel deposits in the world today. Previous preliminary studies by the PI in collaboration with Tony Naldrett (Univ. Toronto) have indicated that mineralization of this deposit, though sulfide saturation, appears to have been caused by contamination of the magmatic intrusion by country rocks. Nonetheless, a smoking gun has not yet been found. This study would expand on previous research by adding high resolution stable isotopic analyses of sulfur, oxygen and carbon from multiple whole rock and mineral separate samples taken from the low-sulfur county rock and unmineralized and mineralized portions of the deposit to elucidate the source of sulfur responsible for sulfide saturation within the deposit.