A distinguishing ore types at the Lac des Iles PGE-gold-copper-nickel mine, Ontario: Implications for resource modelling, mining and processing

• Published in: CIM bulletin Vol. 96; no. 1068; pp. 44 - 47
• Main Authors: MICHAUD, M. J, LAVIGNE, M. J
• Format: Journal Article
• Language: English
• Published: Montréal, PQ Canadian Institute of Mining, Metallurgy and Petroleum 01.02.2003; Canadian Institute of Mining, Metallurgy & Petroleum
• Subjects: Earth sciences; Earth, ocean, space; Exact sciences and technology; Geology; Metal geology; Metallic and non-metallic deposits; Canada; Ontario; Eastern Canada; Ontario Canada; projects; fine-grained materials; gabbros; metals; recovery; distribution; North America; precious metals; mineral assemblages; gold; zoning; copper; petrography; sulfides; nickel; mineral resources; Geology; metallurgy; igneous rocks; deposit evaluation; mining; Ore types; mines; mineralization; Resource estimation; plutonic rocks; platinum group; shear zones; Lac des lles; inclusions; methodology
• ISSN: 0317-0926; 1718-4169

A cornerstone of any successful mining project is an understanding of the mineral assemblage and metal distribution comprising the deposit. Knowledge of the precise mineral/metal zoning enables an operation to utilize different mining and processing methods optimized for different parts of the deposit. The Lac des lles mine, located in northwestern Ontario, is one operation that depends on a good understanding of these issues. Current resources for the Roby Zone total 94.1 Mt grading 1.66 g/t Pd, 0.18 g/t Pt, 0.14 g/t Au, 0.062% Cu, and 0.053% Ni. The Roby Zone occurs within the gabbroic portion of the Lac des lles intrusive complex and consists of three compositionally and texturally different ore types with variable PGE, base and precious metal contents. PGE occur as sulphides and bismuthotellurides in net-textured sul phides, coarse sulphide blebs and as fine-grained inclusions within secondary silicates. Knowledge of the precise mineral/metal zoning has directly and indirectly improved several operational aspects, including resource modelling, mining, and processing. For example, metallurgical recoveries have been increased by up to 3 % to 5% and concentrate grades have increased by up to 100%.