Cutoff Grade Determination for Mines Producing Direct-Shipping Iron Ore
A number of high grade ores such as iron are sold at defined marketing grade specifications. The traditional cutoff grade theory cannot be used with these ores as the direct-shipping grades are fixed by the sale contract. The optimum cutoff grade for these cases is redefined as the grade that maximizes the marketable reserves. A method is described in this paper to determine these optimum cutoff grades for iron ore mines producing direct-shipping ore. An iterative approach is developed which allows the maximization of marketable reserves while maintaining the grades of iron and impurities of silica and alumina within market contract specifications. The larger reserves allow a longer mine lire and increased operation profitability.
O. Mol and S. Gillies, "Cutoff Grade Determination for Mines Producing Direct-Shipping Iron Ore," Proceedings Australasian Institute of Mining and Metallurgy, Australasian Institute of Mining and Metallurgy (AusIMM), Nov 1984.
Keywords and Phrases
Blending; Cutoff Grade; Grade-Tonnage Curves; Iron Ore
Article - Conference proceedings
© 1984 Australasian Institute of Mining and Metallurgy (AusIMM), All rights reserved.
01 Nov 1984