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By R. W. Ruddle

"Besides copper, iron, silicon, and oxygen, a large number of elements may be present in copper ores, the more important of which are zinc, lead, arsenic, antimony, bismuth, selenium, tellurium, nickel, cobalt and the precious metals; impurities of less importance are calcium, magnesium, aluminium, barium, sodium, potassium, manganese, lithium, fluorine, titanium, uranium, vanadium, tin and molybdenum. All of these elements are eliminated to some degree in the subsequent roasting, smelting and converting operations.Information on the elimination of impurities during the smelting of copper is surprisingly meagre, however, rather more information is available on impurity removal during the smelting of the ore in reverberatory or blast furnaces."

Jan 1, 1953

Summary of the morning's events with a Written Contribution to Paper No. 4 and author responses

Jan 1, 1947

For the convenience of those who are unfamilar with thermodynamics, the following brief description and explanation is given of the thermodynamical terms and methods used in this book. It must, however, be strongly emphasized that the account given below is not an introduction to chemical thermodynamics; its sole purpose is to give the reader a rough understanding of the methods used in the earlier chapters. For further information, reference must be made to the standard textbooks on chemical thermodynamics by Glasstone.

Jan 1, 1953

By D. J. Esdale, D. F. Pridmore, F. W. Lindman, J. H. Coggon

Almost all the presently viable nickel reserves in the Yilgarn Block contain nickel in a sulphide phase. Both volcanic peridotite- associated (VPA) deposits and intrusive dunite-associated (IDA) deposits are characterized by massive, matrix and disseminated sulphides (typically, pyrrhotite, pentlandite, pyrite, chalcopyrite, magnetite and other spinels), though in the IDA deposits the volume of disseminated sulphides is far greater than that in the VPA deposits. Potentially all geophysical techniques have application in the direct detection of these deposits'gravity for the detection of the dense massive and matrix ore; magnetics for the detection of magnetite and pyrrhotite in the ores; electromagnetics for the detection of the massive and matrix ore; and induced polarization for the detection of disseminated and to some extent matrix and massive ore. In practice the application of geophysical techniques is limited to a varying extent by (1) the relatively small size of an economic accumulation of sulphides, particularly the VPA deposits, (2) the extreme depth of weathering and lack of outcrop on the Yilgarn Block and (3) the abundance of geological noise or anomalous responses caused by sources other than economic mineralization.

Jan 1, 1984

By A. M. Marabini, S. Battaglia, M. Ciriachi

A computer program has been developed that produces graphic representations of the atomic structure of any crystallographic plane of a mineral. The information provided by the program relates to a purely geometrical model of the crystal structure in which each atom is represented solely by the x, y and z coordinates of its centre. Despite its simplicity, the program can be used as a first approximation model in studies of the interaction between mineral processing reagents and the surfaces of mineral grains which are assumed to be coincident with cleavage planes.

Jan 4, 1992

By A. Hemami

In order to automate the operation of mechanical loaders it is essential to have a knowledge of the forces that act on the bucket and of the trajectory that the bucket should follow. A trajectory for the cutting edge of a bucket is derived from studies of the forces acting during the scooping phase. The proposed trajectory has a minimum energy consumption and is simple to automate. It is determined initially by setting to zero certain components of the resistive forces to the bucket motion which would otherwise result in unnecessary work and consequent energy wastage. The method for finding the appropriate trajectory is discussed on the basis of the properties of the material to be loaded and the loader size.

Jan 4, 1993

By E. A. Brocchi, D. H. Gameiro, P. K. Jena

Carbon tetrachloride was found to be a very efficient chlorinating agent for anatase concentrate, even at the low temperatures that were investigated (250-400 degrees C). For example, at 400 degrees C about 90% of the anatase concentrate was found to have been chlorinated within 60 minutes

Jun 13, 1905

By D. A. White

A simple model for hydrocyclone classification based on the crowding theory first put forward by Fahlstrom is presented. This is a mechanistic theory that postulates that the behaviour of a hydrocyclone is the result of an ordered process that is independent of its dimensions. The main variables that describe the process are the fractions of feed solids and water that are ejected from the underflow. A simple model is developed from basic properties of the classification process and is compared with theory. Agreement is good but improves when the cyclone has a high solids content

Dec 1, 1991

By A. J. Beer, A. Wetherelt

Paper presented at the UK minerals industry conference held in Leeds, UK, 3-5 April 1995. Camborne School of Mines has developed a simple, cost-effective light-sectioning method that has been used successfully in tunnels and small stopes. Light sectioning provides an almost visual examination of the stope's excavated profile. An illuminated section of walls, roof and floor is recorded photographically. Overbreak and underbreak can then be easily quantified by reference to the designed shape. The prototype rig is described. Use of a fish-eye lens to capture a greater field of view is discussed. Calibration was achieved by comparison with images made with a conventional wide-angle lens with nominal distortion. The system is reliable under a range of operating conditions including dust, heat and humidity. It is also simple and easy to use, does not require skilled personnel and is low cost

Jun 18, 1905

Jan 1, 1984

By R. P. Foster, ed.

The short selection of papers in the special issue provides an insight into the level of exploration activity in Africa and the science and technology that are underpinning it. A country-by-country survey is followed by discussion of geochemical exploration in tropical soils, the Liptako region of Niger, structural styles of deposits in Zimbabwe's Bulawayo-Bubi greenstone belt, structural controls in Zimbabwe's Eldorado shear zone, the regional framework for deposits in the Odzi-Mutare-Manica greenstone belt of Zimbabwe and Mozambique, and the Iperindo deposit in Nigeria's Ilesha schist belt

Apr 1, 1996

By P. A. Wright

The note describes the steps involved in the combination of results reported by Shiraishi and Bell in 1968 and 1970 and by Mills and Turkdogan in 1964. Shiraishi and Bell derived from their vapour-pressure measurements an expression for the activity coefficient of tin implying that the miscibility gap in the two-liquid region is symmetrical about the N = 0-5 axis. The limits of the miscibility gap were reported by Shiraishi and Bell and measurements were reported graphically by Mills and Turkdogan. Least-square parabolas are fitted to the transformed results of Shiraishi and Bell and of Mills and Turkdogan for the miscibility gap in the liquid tin-iron system. Back-transformation from these curves gives limits at 1438 K and equations are derived that appear to be a fair average of existing data, although a third term for the activity coefficient equation needs to be investigated

Dec 1, 1971

By G. Richards

Mines are facing fresh challenges over how they deal with the huge quantities of water consumed. industry analyst Frost and Sullivan, demand for treatment equipment and services alone is expected to be worth US$3.6bn by 2016, while a report by consultancy Bluefield Research estimates that the total mine water market - which includes water infrastructure such as reservoirs, pipelines and dewatering systems as well as the equipment and services - will be worth US$17bn by the end of 2019. Methods of water decontamination are described.

May 1, 2015

By Schwartz M.

Madagascar's democratic election has led to a return to its position as a preferred trade partner with the USA and a priority market with Canada. Michael Schwartz takes a look at two key mining projects in this recently reinvigorated country

Feb 1, 2015

By G. R. Chaudhury

Many base metals, such as copper, lead and zinc, are commercially extracted by thermal processing of sulphide concentrates. However, owing to the depletion of high grade sulphide ore reserves and to environmental legislation, efforts have been in progress for some years to develop methods for the extraction of metals from lower-grade oxide ores and secondary resources, and there are now examples of commercial-scale operations.

Dec 1, 1995

By A. Sutherland Strachan

Before regulations governing the work on the mines, it was not uncommon in the Rand for a miner to die within a period of 2-3 years as the result of exposure to dust. This paper considers mine and tunnel conditions promoting silicosis and measures to avoid dust exposure in the Rand, South Africa.The relationship between blasting and lung lesions is explored. Evidence is presented that improved working conditions and lowered dust levels reduce the incidence of silicosis.

Jan 1, 1947

By G. H. Blackwell

Sequences in open pit mining must be planned and regularly revised to incorporate changes in the variables which affect profitability. Interactive computer planning with colour graphic facilities is an effective tool for this purpose in the short and medium term. An interactive computer planning system for medium-size, low grade porphyry copper-molybdenum open pits is described. The planning system proved especially valuable during the critical stages of pushback mining when deep, inner pit ore was nearly depleted and the erratic grades of the next pushback provided ore and marginal material at a time of depressed metal prices.

Jan 8, 1993

By P. Danson, D. A. White, S. Bashir

Composite ion exchange materials made of SnO2, TiO2 and MnO2 can be used to remove radioactive contaminants from nuclear waste streams. In several cases their selectivity and capacity are enhanced by mixing hydrous silica into the matrix. MnO2-SiO2 materials are especially useful for a number of reasons, such as their selection of heavy elements over caesium. Distribution constants and determinations of exchange capacities show that in many instances the properties of the composites are better than those of the oxides alone, while the presence of a chelating agent has been found to reduce the uptake of nuclides considerably. Methods are being developed for the bulk manufacture of the materials. Further work on sorption mechanisms is required to explain anomalous results, particularly the variation in exchange capacity for different elements and the ability of the oxides to sorb colloidal material in alkaline solution.

Jan 8, 1992

By E R. Hassall

Discussiong the importance of minerals and mining, impacts on the environment and remediation, and the need to foster interest in science among young people.

Jan 8, 1997

By D. F. Ball, P. R. Dawson, J. T. Fitton

Report of discussion at December, 1970, IMM general meeting (Chairman: M. J. Cahalan, President) and contributed remarks on the paper published in Transactions/Section C (Mineral Processing & Extractive Metallurgy), vol. 79, September, 1970, pp. C189-96, plus the authors' replies. Contributors included Cohen E., Hope B., Wasse D.G., Shakespeare A.G., Burwood D.S., Jones H.A., Dartnell J., Carter G.C., Henderson T.A., Relf G. and Clark S.W.

Dec 1, 1971