Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

In most magmatic ore deposits, platinum-group elements (PGE) are found within the structure of base-metal sulphides, and are associated with Te, As, Bi, Sb or Sn (TABS) in the form of platinum-group minerals (PGM). The origin of these PGM is important in understanding how the PGE are concentrated. Based on the distribution of the PGE and TABS between PGM and base metal sulphide minerals from the Noril’sk-Talnakh ores we conclude that: i) For the ore formed from the least fractionated sulphide liquid (Cu-poor), insufficient TABS were present in the sulphide liquid for PGM to crystallise, and consequently, the PGE and TABS are present in the base metal sulphide minerals: ii) For ores formed from more fractionated sulphide liquids (Cu-rich), TABS concentrations in the liquid rose sufficiently for PGM to crystallise, and consequently, approximately half of the PGE and TABS are present in the form of complex PGM intergrowths.