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By J. E. Miller

The development of a new means of measuring the relative abrasivity of a slurry came about by necessity in 1967 during a full scale loop test of a 560 H.P. reciprocating pump handling magnetite slurry. In order to evaluate the life of expendable fluid end parts, the question of the amount of attrition in a re-circulated slurry had to be considered. An expected reduction in abrasivity as a result of this attrition would certainly give erroneous data on a parts life test. There- fore, some means of measuring such change in abrasivity became imperative. Several test methods were investigated1 but it was felt that these did not fully represent the wear due to back and forth rubbing action associated with a reciprocating pump. A "rubbing block" device used some years ago to determine the quality of hard facing materials was recalled, along with its shortcomings, in that an attempt was made to suspend a small percentage of abrasive particles in a colloidal viscous "mud". Erratic results were attributed to the fact that it was difficult to maintain a consistent slurry concentration under the metal wear block and the reciprocating speed was not great enough to maintain good agitation.

Jan 1, 1973

"The McArthur River uranium deposit is the single richest uranium ore body developed in the world to date. The ore body’s average grade is 15% U3O8. Proven reserves are in excess of 450 million pounds. The grinding circuit is located underground. The ground ore is pumped to a surface facility where the slurry is thickened and loaded into containers for shipping to the Key Lake mill 78 kilometers to the south.The paper will briefly describe the mining method employed. The underground ore handling and grinding circuit, and surface facilities including slurry load out, wastewater treatment and the freeze plant will be described in detail. The paper will emphasize radiation and safety procedures that are followed to minimize operator exposure to radiation risks.LOCATIONThe McArthur River mine is located 78 kilometres north of the Key Lake mill. It is located at latitude 57’ N in northern Saskatchewan, within the southern boundary of the Athabasca formation. The nearest town is Pinehouse, located 320 kilometres to the south. Access to the mine is by an all weather road and by a private airstrip.HISTORYThe McArthur River Operation is jointly owned by Cameco Corporation (69.805%) and Cogema Resources Inc. (30.195%). Exploration for uranium in the McArthur River area started in 1980 by the Saskatchewan Mining Development Corporation, a predecessor company of Cameco.In 1984, a 12-kilometre long basement conductor was identified at a depth exceeding 500 metres. Systematic exploration drilling of this conductor resulted in the discovery of the P2 North deposit. Subsequent surface drilling programs from 1989 to 1992 delineated a narrow ore zone over a strike length of 1700 meters at a depth of 500 to 600 metres. At this time, geological reserves for the deposit were estimated to be 2.4 million tonnes at a grade of 5.0% U3O8 for a uranium content of 260 million pounds U308"

Jan 1, 2001

By Vas P. Srinivasa

A comminution circuit is an important integral part of a mineral processing plant. Nearly 40% of the capital cost and 30 to 40% of the operating cost are taken up by the crushing and grinding circuit. Therefore, considerable care should be given to the design and selection of this circuit. Several factors affect the selection of a comminution circuit--energy consumption, avail- ability of the equipment, the remoteness of location, and availability of trained personnel, to mention a few. Each of these factors influences the choice. Selecting a comminution circuit strictly on lower capital cost may not be optimal. Crushing and grinding circuits are usually site specific and should be selected - only after careful analysis of all the factors involved. The objective of this paper is to show the effect of these factors, which are extranious to capital cost. Usually, the capital cost of a semiautogenous grinding circuit is lower than that of an equivalent conventional circuit. However, due to lower equipment availability and high power costs in certain locations, the economic advantage of lower capital cost is lost. Analysis indicates that a break even point occurs at a power cost of 5¢/kWh. This paper describes the procedure utilized for selecting the most economic comminution circuit and states the conditions applicable for each cominution circuit.

Jan 1, 1983

By K Nilsson, G Cheong

Troy Resources NL acquired a 70 per cent interest in the Mina Sertpo gold project in Goißs State, Brazil, in 2001 following a successful bid for the highly competitive international tender of a tenement package put out by Western Mining Corporation (WMC). The Sertpo deposit is located on cleared grazing land 380 km west of Brasilia and is 30 per cent owned by Amazonia Mineracao Ltda, a private Brazilian company. It is a small high grade open-pittable orebody with a measured and indicated resource of 108 000 tonnes at a grade of 49.7 g/t for 172 500 ounces using a 2.0 g/t cut-off. Troy undertook the project management and development of the project while Amazonia managed the exploration activities and provided other services as required. The project development involved drilling metallurgical test holes, scouring the world to locate an available and suitable second-hand plant, and arranging shipping to andreconstruction in Brazil.

Jan 1, 2004

By K. Short

Today?s modern mining operations have literally dozens of applications and systems generating data whose information very often, are not crossed or centralized for operational decisions. In remote locations, the information and situation awareness is typically limited to the location itself. In addition, access to that information is limited to a small, select group of personnel that have received training on how to interpret the results. When the situation affects another area of the mine then information is relayed to the applicable areas involved. Few workers have time to analyze the situation thoroughly, to see how it affects the mines symbiotic relationship within all areas of production. If the capability to correlate and measure events and situations that affect your overall key performance indicators are not in place, the opportunity to identify process improvement becomes more difficult.

Feb 27, 2013

"The Mine Haul Road Optimization Alliance is an Australian industry-academia collaboration which has been developed to support mine haul road operators by fully integrating mine road design research solutions with industry end-user service providers to design, assess, implement and monitor the various equipment, materials and road management strategies required to optimize the safety, environmental and economic performance of a haul road. Initially, a broad overview of the university-industry collaborative landscape is presented, following which the current situation in the Australian mining sector is reviewed both nationally, and on a country-wide basis, internationally. This insight places realization of a collaboration between Curtin University Western Australian School of Mines Mining Engineering and Metallurgical Engineering (WASM ME2) and the Haul Road Optimization Alliance (HROA) industry members into context of opportunity. Following an overview of the HROA collaborative structure, aims and objectives, it is shown how academia and industry can collaborate to deliver a more robust solution to mine haul road design, performance or management needs, especially where integrated solutions are needed. Critically in this approach, implementation and monitoring data provided by industry and service-providers alike forms the foundation on which to develop research knowledge and innovation that is more responsive to the end-user requirements, typically represented by ‘early goals’ and implementable solutions. The paper concludes with examples of how the alliance collaborations work in practice to deliver improved mine haul road designs and optimized operational performance, together with the mechanisms used to ensure industry needs are met through focused, end-user driven research and integrated solutions implementation."

Jan 1, 2016

By D. G. Sinclair

In any discussion on the subject of mine-safety, it is well to honestly face the fact at the outset that mining is a hazardous occupation and that certain inherent dangers attach to the work, which, in spite of the greatest vigilance on the part of everyone concerned, will from time to time exact their toll of in jury or death from the underground worker. Great progress has been made of late years in narrowing down the range of these necessary risks, and, illustrative of what can be done along these lines by concerted effort, it is pleasing to read from time to time of large operating mines running for weeks, months, a year or more, without a single lost-time accident. To achieve any results in the work of accident prevention it is necessary, first, to have a definite goal, such as a no-accident period, be it a week, a month, or a year, to aim at; and, second, to set up definite standards to work by. The legal code of regulations should form the basis of all standards of work at every mine and should, for this reason, cover as far as possible all conceivable phases of operation. This represents the ideal, but in practice it is unattainable, largely because of the many variables that must be considered, due to the divergence in the scale of operations and to differing geological conditions at the different mines. Hence it becomes necessary for the operator who wishes to attain the maximum in the establishment of high standards of safe operation to so amplify the code as to meet the peculiar requirements of his operation.

Jan 1, 1930

The labour question is one that has caused mine managers much thought and anxiety and is likely to continue to do so as long as human beings exist. The difficulty is to devise some arrangement whereby the interests of miner and mine ownerare identical. Mines cannot be worked without capital, and capital is no good without labour, yet, though both have the mine in common, their interests are not exactly the same. Some men are happy so long as they can scrape through by exerting themselves as little as possible, but capitalists do not work mines for charity, they want some return for their money.Where a large number of men are employed there are bound to be examples of all sorts, good and bad, and it is because one cannot depend on all, that different methods of employment have to be adopted. Which method is selected depends to a great extent on the labour market, local conditions, nature of the ore and the way in which it occurs.A big step towards success is obtained by securing the services of good bosses, not only those who know how work should be done, but men who have a knowledge of human nature. It is a big mistake to be too lenient with a man, also to be unnecessarily harsh. A good boss will always be sought out by good men who have worked under him before, or who have heard of him from others. By a good boss we do not mean one who employs two men where one would do, or who lets the men loaf...

Jan 1, 1901

By R. L. Grayson

Productivity achievements in underground coal mining over the past ten years highlight the improvement of management practices as well as the adoption of new technology. Research findings and results from operational studies characterize the aspects of good management that translate into high productivity. In concert with these findings, the Mine Management Support System (MMSS) is being developed, under co-sponsorship of the U.S. Bureau of Mines and the West Virginia University Energy and Water Research Center, as a knowledge-based system to enhance more efficient management of underground coal mines. Concentrating on capturing the intricate knowledge needed to manage a mine effectively, MMSS will encompass information and rules on work scheduling, desired work practices, regulations impinging on operations and planning, responses to operating problems, and the labor-management work agreement.

Jan 1, 1990

The operations management system at Olympic Dam has evolved over a two-year period to the state described in this paper. This evolution has been driven largely by the requirements of the recent expansion of the Olympic Dam operation from three to nine million tonnes of ore per year. Such a change process demands an holistic approach to mine management and several techniques have been employed including XPAC, Mine Works Planner as well as a basic philosophy of æjust-in-timeÆ completion. The philosophies, software and tracking mechanisms for managing a large tonnage operation are described, outlining a fully integrated scheduling system from shift to shift detailed activity planning to a 20 year production plan. Moreover, the vision of production exceeding the current limit of nine million tonnes means that there are to be further developments to this state-of-the-art system in use at the Olympic Dam mine.

Jan 1, 2000

By Robin B. Batterham

"Since the 1970?s we have seen a marked corporate response in terms of the environment. In part this has come from regulation but it has largely come from stakeholders and the community. Rising expectations have in general been met. We now see a similar trend towards sustainability. At the same time, the importance of mining to the share market has decreased drastically and with that decrease has come the requirement for the mining sector to show returns similar in manner to other sectors. While rationalisation can achieve some progress towards these goals, the long-term requirement is for innovation, as it always has been. This paper looks to the logical goal of innovation within a sustainable mining framework and targets the removal of the desired metal values with minimal environmental footprint. It is suggested that broad ranging alliances will be necessary, particularly amongst the R&D suppliers, to achieve this goal. Industry will need to take an active role given the recent global restructuring.THE MARCH TO SUSTAINABILITYSince the 1970?s there has been an increasing corporate response on environmental matters. We have moved from matters environmental being issues relevant only to minority groups through a series of attitudinal changes by management. Whilst there have always been examples of excellent environmental performance, for many in the 70?s spending money on improving the environment beyond some minimal level was seen as a distraction from production or treated in a similar way to donations to the community. There is little of that attitude these days, as most mining companies have long since regarded the environment as a core business direction. Indeed, for some years one could note an escalation in matters of environmental reporting to the extent that the environmental performance of companies is now very public. In some cases, NGOs have even been invited to help certify and audit the reporting standards. Similarly with health & safety.There is now a rising expectation on the part of the community that social matters will also be given the same level of support as health, safety and the environment. This time around it would appear that the mining industry is at the leading edge of sustainability. The Global Mining Initiative (Global Mining, 2002) and the contributions to the Rio World Summit on Sustainable Development (Rio +10, 2002) suggest that sustainability is being taken very seriously by the mining industry. For sustainability it is convenient to use the Brundtland (1987) definition. This definition has widespread acceptance with governments, industry, environmental groups, financial institutions and individuals as a direction against which our activities and plans can be measured."

Jan 1, 2003

By L. E. Beverage

In 2006, the Mine Improvement and New Emergency Response Act (?2006 MINER Act?), Pub. L. No. 109-236, 120 Stat. 493 (2006) was enacted in a bi-partisan move to strengthen the 1977 Mine Safety and Health Act. This action followed several underground coal mining accidents at the Sago and Aracoma Mines in West Virginia and the Darby Mine in Kentucky. The focus of that legislation was, in part, to force technological development and implementation. It involved the recomposition and training of rescue teams. Requirements for sealing worked out areas of mines were changed when MSHA invoked its Emergency Temporary Standard (?ETS?) authority for the first time in many years. Increased penalty amounts were established for certain types of violations for all types of mining, and minimums were set for unwarrantable failure violations issued under Section 104 (d)(1) and (d)(2); 30 U.S.C. Section 814 (d)(1),(2). The entire 30 C.F.R. Part 100 penalty criteria was revamped in a rulemaking, effective in April 2007. The visions were ambitious and noteworthy and those in industry and government have spent the last four years working through the aftermath of intended and unintended consequences of these changes. The penalty structure arrived at in 2007 has proven unwieldy and has contributed to the increase in contested caseload now before the Federal Mine Safety and Health Review Commission. In essence, litigation under the Mine Act ground to a virtual halt when the number of cases increased but the budget for Administrative Law Judges, who hear the cases, and the Solicitor?s office who represents MSHA, was not increased. Addressing the backlog effectively was one of the major challenges when Joe Main was confirmed as Assistant Secretary in early 2010.

Jan 1, 2011

By F. T. Cawood

Inauguration of the new political dispensation in South Africa in1994 initiated a dynamic shift in the ownership, management and development of the country?s affluent mineral heritage. The process of substituting the old South African regime with a new equitable system started soon after the 1994 election of the African National Congress (ANC) to parliament. The Congress?s Freedom Charter revealed the intent of the new dispensation when it called for radical transformation of mineral development. However, since then there have been important changes affecting the rules of mineral development. These are: ?A drastic change in politics ushered in by negotiation, a spirit of reconciliation and a desire to settle disputes peacefully ?The globalization of the South African mining industry in tandem with the opening of domestic mineral resources to foreign capitalists and ?The introduction of sustainable development as a holistic approach to mineral development in order to replace traditional narrow-minded environmental management. Each of these significantly shaped the new mineral investment environment of South Africa. This paper represents a summary of the historical developments leading to the current Mineral and Petroleum Resources Development Act No. 28 of 2002, its regulations, the much publicised Broad-Based Socio-Economic Empowerment Charter, its associated Scorecard, and the Draft Royalty Bill.

Jan 1, 2004

By F. T. Cawood

This research report was produced in response to the release of the Mineral and Petroleum Royalty Bill. It involved are view of the mineral investment environments of selected countries in order to form an opinion on the appropriateness and competitiveness of the proposed royalty structure for South Africa. Many emerging countries have recently attracted a significant share of foreign investment, as a direct result of changes in policy. These are, by implication, the least risky and most favourable destinations for the ?investment dollar?. The five most competitive countries, namely Chile, Argentina, Peru, Mexico and Brazil have been identified as succeeding with their policy visions of creating favourable domestic investment environments. The investment rules of these countries served as a basis for the compilation of a Competitive Investment Framework (CIF). This is a template of best practice against which other investment environments, such as that of South Africa, can be measured. The framework indicates that mineral royalties should ideally be no more than three per cent, demonstrating that the regime proposed in the Royalty Bill is out of step with international best practice. Mineral royalties can never be viewed in isolation and in the assessment of the rates proposed in the Royalty Bill, one must consider the total taxation package. Such assessment appears in Section 5 of this report, demonstrating that there is reason for concern if National Treasury were to impose the rates stipulated in the Royalty Bill. The alternatives, conclusion and recommendations of the review appear in Sections 9 and 10. These are the result of independent analysis and assessment of the fundamental principles. It is done through the application of a Competitive Investment Framework that avoids the highly subjective and emotional views that often accompany a process like this.

Jan 1, 2003

By Edwards A. B

The following note on the mineral association in the ores of the Tennant Creek Goldfield, Northern Territory, is largely based on Mineragraphic Reports Nos. 49, 89, 117 and 193 of the Council for Scientific and Industrial Research. These reports are the results of the examinations of auriferous specimens from a number of mines of the goldfield and are now supplemented by the examination of further specimens from Mt. Samuel forwarded by Mr. V. G. Martin.The Tennant Creek Goldfield lies in the central portion of the Northern Territory, about Lat. 190 35', Long. 1340 15', on the Overland Telegraph Line and about 369 miles north of Alice Springs. It comprise an area extending about 50 miles east and west, by 30 miles north and south.The geology of the goldfield has been described by Woolnough. (2)The rocks of the area are of pre-Cambrian age, and consist of talcose, chloritic, micaceous and siliceous schists of sedimentary origin, interbedded with flows or dykes of schistose quartz porphyry, and of granites which were intruded subsequent to the regional metarporphism of the area. The rocks are moderately folded, but the beclding tends to be obscured by a pronounced east-west cleavage. The most continuous orebodies run east and west, parallel with this cleavage.Numerous lenses of hematite occur in the schists, with their long axes, parallel to the cleavage, and the gold values of the field are frequently associated with such hematite bodies. The dimensions of these hematite bodies are variable but rarely exceed a length of 300 ft., with an average thickness between 10 and 30 ft.; the original vertical dimensions are thought to be comparable with their length. The lenses tend to occur in groups when they are arranged en echelon both horizontally and in depth; and erosion has exposed individual lenses to different degrees, ranging from incipient exposure to complete removal. The existence of unexposed hematite lenses at depth has been proved by geophysical surveys, coupled with drilling tests. (3)A few of the bodies are pipe-like. Many are surrounded by a casing of brecciated rock, composed of fragments of hematite and shattered country rock, and presumably caused by subsequent earth movements which crushed the country rock against the resistant hematite bodies. In the early days of the field most of the important gold occurences were found within these crushed zones, or, to a less extent, within the hematite bodies themselves.These occurrences appeared to be associated only with those hematite lenses which were intersected by quartz veins or other lines of weakness, of later origin than the crushing. This led Woolnough to think that the introduction of the gold and attendant bismuth was subsequent to the...

Jan 1, 1942

Ore from the Hill 50 Gold Mine, consists essentially of pyrrhotite, with minor amounts of pyrite, chalcopyrite, galena and gold, replacing "jaspilite." The gold is associated with the sulphides as shotty particles. About 8 per cent. of the particles are less than '0.010'mm.The Hill 50 Gold Mine, at Boogardie in the Murchison goldfield, about 300 miles north-west of Kalgoorlie, was first operated in 1898. From 1898 to 1917 it yielded 20,000 short tons of ore for a recovery of 6,225' fine oz. gold, equivalent to a recovery grade of 6.22 dwt. gold per ton.The present company since the beginning of its operations in September 1936 to June 30, 1954, produced 811,081 short tons of ore for a recovery of 242,554 fine oz. of gold, equivalent to a recovery grade of 5.98 dwt. gold per ton.The grade of ore (recovery grade) has shown a remarkable variation with depth. From the 120 ft. Ievel to the 300 ft. level, it averaged about 7.5 dwt. Au per ton. Below the 300 ft. level it declined, and from 300 ft. to 400 ft. averaged 4.9 dwt. per ton, falling further with increasing depth to about 4.5 dwt. per ton at the '600 ft. level.On the 820 ft. level the grade improved sharply to about 14 dwt: per ton, and this grade has persisted down to and on the 1060 ft. level.The orebody has been described by Finucane (1953) as a series of lenses of finely banded jaspilite conformably enclosed by greenstones. The jaspilite is tightly folded and faulted and intruded by dykes of felspar porpnyry.Mineralization is practically restricted to the jaspilite.

Jan 1, 1955

By Edwards A. B

A suite of specimens from the newly developed Black Star copper ore body at Mount Isa was made available for mineragraphic study by the Mount Isa Mines, Ltd. The specimens were selected as representative of the different phases of mineralisation found in the ore body, rather than with a view to furnishing a complete cross-section of it; and the examination has been carried out with a view to ascertaining (1) the nature, extent and association of the arsenic, antimony and possibly bismuth, minerals in the ore, (2) the mode of occurrence of silver in the ore, and (3) whether galena and sphalerite occur in minute forms well below the sIzes readily observed in hand specimens.Analyses of the January to June, 1944, mill head composites show that the proportions of the elements Ag, As, Sb and Bi in the ore are as follows:Ag 0.000013 = 0.35 oz./tonAs 0.024Sb 0:002Bi 0.0005The copper content of the mill heads ranges from 3.5% to 4.75%, the lead content from 0.03% to 0.08,% and the zinc content from 0.09% to 0.23%.MINERAL COMPOSITIONThe specimens range from massive sulphide ore, consisting of areas of chalcopyrite, pyrrhotite, and rarely sphalerite, from 1 to 3 cm. across, to fragments of extremely finely banded pyritic shale in which no minerals other than pyrite are visible. The gangue associated with the massive sulphides is chiefly dolomite, and sometimes white quartz. The pyritic shale fragments show evidence of shearing and faulting on a micro-scale, the fractures sometimes being filled with sulphides and vein minerals.The ore minerals found in the polished sections are pyrite, arsenopyrite, marcasite, sphalerite, chalcopyrite, valleriite, chalcostibite, galena, dyscrasite, jamesonite, magnetite, gold, graphite and rutile.Pyrite (FeS2)Pyrite occurs chiefly in two forms according to whether deposition took place along the bedding planes or along the intersecting faults and fractures. Deposition of pyrite along the bedding planes of dense, thinly banded shales ha,s produced a metasomatically altered shale in which the pyritic bands are from 0.02 to 0.03 mm. wide, and alternate with bands...

Jan 1, 1945

The silver-lead ores of Yerranderie occur in a series of narrow, flat-dipping lodes in small bodies of quartz porphyry, intrusive into Upper Devonian volcanics, which are exposed in the western flank of the Permo-Triassic Basin of central New South Wales, about 80 miles south-west of Sydney (Harper, 1930; Lawrence, 1953). The lodes strike about E.-W. and are from 1,200ft. to 2,000ft. long. They consist of a series of ore shoots from 3ft. to 100ft. long, and up to 5ft. thick, though commonly under 2ft. thick, interspaced with low grade sections. They dip at from 18°S. to 400 S., and have persisted down the dip for 1,450ft. (693ft. vertical depth) in the Wollondilly mine, for 1,120ft. in the Bartlett's mine, and for 850ft. in the Wonga mine.The grade of ore in the Bartlett's mine was from 32% to 40% lead, from 100 oz. to 130 oz. silver per ton, 0.5 to 4.0% arsenic, with ore ,as rich as 20% arsenic on the No. 6 and No. 7 levels of the Silver Peak mine, the underlay extension of the Bartlett's lode, about 1% copper, and up to 4 dwt. gold per ton. In the Wollondilly mine the average grade was 15% lead, with sections as rich" as 36% lead, from 75 to 165 oz. silver per ton, 0.6 to 3.3% arsenic, 0.2 to 0.7% antimony, 0.8% copper, and up to 7...5. Cl~t. gold per ton. The zinc content of the ores is slight, and has not been recorded.Mining began about 1898, and to date more than 110,000 tons of ore, valued at £1,800,000, has been raised. Large scale mining ceased about 1935. The chief mines operating were the Bartlett's mine (formerly Colon Peak), the Silver Peaks, which is the underlay extension of the Bartlett's, the Wollondilly (or Yerranderie) mine, and the Wonga' (or Tonalli) mine.

Jan 1, 1953

A concise country-by-country summary of the mineral industry of Africa is presented. Reserves, resources, role of the country in the world mineral supply, and developments in the mineral industries are reviewed. The data on each country are accompanied by a map showing mineral location and transportation facilities.

Jan 1, 1976

By George A. Morgan

The 53 countries that constituted Africa in 1991 accounted for a significant portion of total world output of a number of mineral commodities. However, total output for the continent declined for many major mineral commodities produced compared with that of 1990. Also, Africa's share of total world output of these commodities generally declined. (See tables 1 and 2.) The most conspicuous declines were for cobalt and copper owing to mining and metal processing difficulties experienced by the world's two largest cobalt producers, Zaire and Zambia. Phosphate rock output declined primarily owing to a sharp fall in production from Morocco, also a leading world producer. Morocco's state corporation for phosphate production experienced marketing problems, leading to the decline.

Jan 1, 1993