Ore-reserve estimations of deposits with low mineral concentrations, such as those of copper, gold and tin, are usually made on the assumption that the grades follow a lognormal distribution. Multiple mineralization or reworking of a deposit may have modified the simple distribution expected — producing an overall distribution of grades which can be adequately described by a mixture of lognorma...

The surface geochemistry techniques widely employed during the 1960’s to 1980’s are effective at discovering near-surface deposits, but are largely ineffective for exploring under deep cover or for deep extensions of known mineralisation in a near-mine environment. Instead, mineral explorers must focus their attention on rapidly aggregating and synthesising disparate data to build into holistic...

This study deals with application of artificial neural networks (ANNs) on grade control at mine sites inputting both geological and geotechnical variables. Case study is Chapada copper-gold deposit (Goiás, Brazil), located in the neoproterozoic Chapada-Mara Rosa volcano-sedimentary sequence. Ore is closely related to hydrothermal alteration, structurally controlled. The geological and geotechni...

The Qulong porphyry copper and molybdenum deposit is located at the southwest margin of the Lhasa Terrane and in the eastern region of the Gangdese magmatic belt. It represents China’s largest porphyry copper system, with ∼2200 million tonnes of ore comprising 0.5 % Cu and 0.03 % Mo. The mineralization is associated with Miocene granodiorite, monzogranite and quartz-diorite units, which intrude...

The most important examples of magmatic ore deposits in volcanic rocks are Fe-Ni-Cu-(PGE) sulphides associated with Archean and Proterozoic komatiitic lava channels (Lesher, 1989). Komatiitehosted ores contain ~25% of the world’s nickel sulphide resource (≥ 0.8% Ni), including significant amounts of copper and platinum group elements (Ross and Travis, 1981). Field, experimental, and theoretical...