PGE V-Voisey's Bay (Canada) D -Duluth Complex (USA) K-Kambalda (Australia) M-Merensky Reef (Bushveld) N -Noril'sk region (Russia) P-Pechenga(Russia) S-Sudbury (Canada) T-Thompson (Canada) J -Jinchuan (China) L-Lac des lies (Canada) PR-Platreef (Bushveld) Po-Portimo Complex (Finland) R-Raglan (Canada) U-UG-2 chromitite (Bushveld) Z-Great Dyke of Zimbabwe e-Mt Keith (Australia) . a. -Perseverance (Australia) +-Stillwater (USA) 0 0 0 'c9 -~ Ni+Co Cu Relative value of Ni+Co Fig. 1. 1. Relative va1ue of the contributions of Ni+Co, Cu and PGE to the mag- matic su1fide deposits listed in Table 1. 1 sulfide deposits are closely related to bodies of mafic or ultramafic rock, and the most convenient way in which to consider them is in terms of the type of magma responsible for the rocks with which they are associated. Typically the type of magma involved bears a close relationship to the tec- tonic setting within which it was emplaced. The locations of important deposits, both Ni-Cu dominant and PGE dominant, are shown in Fig. 1. 2. Considering first Ni-Cu deposits, these are further divided into six classes (Table 1. 2) on the basis of their associated magma type. Class NC- 1 (Chap. 3) comprises those related to komatiitic magmatism. Currently known deposits fall into two sub-classes, those related to Archean komatiites ( e. g. the deposits of Western Australia, Zimbabwe and the Abitibi belt of Canada) and those related to Proterozoic komatiites (e. g. those ofthe Raglau and Thompson belts which arebothin Canada)l.

Copper belongs to those metals whose concentrations in nature arise from a broad diversity of endogeneous and exogeneous pro- cesses, which applies to essentially all genetic classes of ore deposits. This is the first proceedings volume on copper metallogeny to cover the worldwide distribution of the four main groups of cop- per deposits, including in Part I: copper-nickel deposits with cobalt and platinum group elements; Part II: copper-molybde- num-gold deposits with silver, zinc, and lead; Part III/IV: copper- zinc-lead deposits (with silver etc.). On the occasion of the 27th International Geological Congress in Moscow, USSR, a symposium on copper metallogeny was held, dealing with metallogenesis and mineral deposits. The symposium was organized and sponsored by three international societies en- gaged in the field of ore deposits: The Society of Economic Geol- ogy (SEG), the Society of Geology Applied to Mineral Deposits (SGA) and the International Association on the Genesis of Ore Deposits (IAGOD). Invited papers were presented in four ses- sions: (1) Copper deposits in mafic and ultramafic complexes, (2) Porphyry copper deposits, (3) Copper deposits of volcanic-hydro- thermal association, and (4) Sediment-hosted copper deposits. The sessions were chaired by A. D. Genkin, A. J. Naldrett, J. D. Ridge and G. I. Gorbunov; V.1. Sotnikov, A. Soregaroli, R. H. Sillitoe and V. A. Evstrakhin; F. M. Vokes, A.1. Krivtsov, M. Solomon and N. I. Eremin; G. H. Friedrich, Yu. V. Bogdanov, A.C. Brown and F.P. Krendelev.