 Pyrite and sphalerite are the main sulfide minerals found in the 120 m thick volcanic conglomerates and agglomerates, which constitute the world's second largest sulphidation gold deposit.Between Bonao and Maimón, Falconbridge Dominicana has been mining nickel laterites since 1971.The Cerro de Maimon copper/gold open-pit mine southeast of Maimón has been operated by Perilya since 2006.