ABSTRACT
Base metals broadly refer to a category of non-ferrous metal commodities typically consisting of copper, nickel, cobalt, lead, zinc and mercury (Craig and Vaughan, 1990; Jones, 1999; Cole and Ferron, 2002; Crundwell et al., 2011; Schlesinger et al., 2011). Although the platinum group metals (PGMs) (also referred to as platinum group elements (PGE)) are technically classified as precious metals, they are mostly associated in nature with base metal minerals such as copper-nickel-cobalt-iron sulphide minerals. Furthermore, the primary production of PGMs is closely associated with the production processes of copper, nickel and cobalt metals, hence their inclusion in this chapter (Jones, 1999; Cramer, 2001; Cole and Ferron, 2002; Crundwell et al., 2011).
